On 40

This post is about the number forty, quaranta, veertig, cорок, keturiasdešimt, Minn erbgħin, XL, and many more … can you add any?

40 – As forty, the only English number with the letters of its correct spelling are in alphabetical order

In Mathematics
40 – a composite number, an octagonal number, a semiperfect number, a Harshad number, a Stormer number

40 – divisible by 1, 2, 4, 5, 8, 10, 20, and 40

In Science
40 – the atomic number of zirconium, whose neutrally charged atom has 40 protons and 40 electrons

40 – the number of weeks for an average term of pregnancy

M40 – a star in the constellation Ursa Major

NGC 40 – a planetary nebula in the constellation Cepheus

In Religion

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  • 40 – a commonly used time period (days, nights, years) – (many references)
  • 40 – the number of days and nights during the Flood
  • 40 – the number of se’ah in a mikvah of water (approximately 200 gallons/757 liters)
  • 40 – the number of lashes as a punishment


  • 40 – the number of days and nights Jesus fasted
  • 40 – the number of days between the resurrection of Jesus to the ascension of Jesus
  • 40 – the number of days of Lent preceding Easter (but Eastern and Western Christianity count it differently)


  • 40 – Muhammad’s age when he first received the revelation delivered by the archangel Gabriel
  • 40 days – the official length of mourning


  • 40 – the number of stanzas (shlokas or dohas) in some popular HIndu prayers
  • 40 – number of days fasting

In Sports

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40 – number of players allowed under contract for each MLB baseball team

40/40 Club – Players achieving 40 stolen bases and 40 home runs in a season (only been done 4 times)

40 – the maximum number of horses in the grand national

40 yards – (36.5 meters): the distance dash as a metric in scouting American football players
The distance run in the 40 yard dash, an important metric in American football scouting.

40 – the third point in a tennis game … and 40-40 is called “deuce”

40 – the number of cars in a NASCAR Nationwide race

40 – the number of a NASCAR car that has won 9 races by drivers Sterling Marlin (4), Pete Hamilton (3), Tommy Thompson (1), and Jamie McMurray (1)

40 – a jersey number retired in this professional sports:
MLB: Don Wilson (Astros), Danny Murtaugh (Pirates)
NBA: Byron Beck (Nuggets), Bill Laimbeer (Pistons)
NFL: Pat Tillman (Cardinals), Gale Sayers (Bears), Mike Haynes (Patriots), Joe Morrison (Giants), Tom Brookshier (Eagles)

In Entertainment
40 – the number of spaces in a standard Monopoly game board

40 -the highest number ever counted to on Sesame Street

In Music
Crush 40 – an American-Japanese hard rock band

“40” – a song by Dave Matthews Band, UC, and Franz Ferdinand

“Forty Shades of Green” – a song by Johnny Cash

40 – the name of Canadian hip hop producer Noah Shebib

Symphony No. 40 – by Haydn and Mozart

40 – the number of song on popular weekly radio programs as American Top 40, Rick Dees’ Weekly Top 40, and American Country Countdown – #1 40 years ago today

In Television
$40 – the spending limit for chefs on “Chef on a Shoestring”

$40 – the per day spending limit on $40 a Day, a travel/eating show originally on Food Network hosted by Rachael aye

In Literature
40 – the number of thieves involved with Ali Baba in Arabian Nights

In Culture
To understand a people, you must live among them for 40 days. ~Arabic proverb

40 hours – the customary number of hours in a regular workweek in some countries

40 days – Russian folklore regarding the length of time ghosts of the dead linger at the site of their death

40 years – an age milestone

40th wedding anniversary – Ruby is the traditional gift

In US History
40 acres and a mule – a plan to offer freed slaves after the US Civil War

40th US President – Ronald Reagan

STS-40 – the 11th mission of the Space Shuttle Columbia (June 1991)

Federalist Paper No. 40 – written by James Madison about the authority of the Constitutional Convention

In World History
40 – During the Bubonic plague, the number of days ships isolated in the harbor before passengers could go ashore

40 – another name for The Tessarakonteres, the largest ship of antiquity, constructed by Ptolemy IV of Egypt

40 CE

  • Korean calendar year 2373, Holocene calendar year 10040, Discordian calendar year 1206
  • A leap year starting on Friday
  • Roman Emperor Caligula starts on a campaign to conquer Britain (which failed)
  • The Vietnamese Trưng Sisters rebel against the rule of the Chinese Emperor Guangwu of Han
  • Philo teaches that all men are born free.
  • Christianity comes to Egypt

40 BC

  • Assyrian calendar year 4711, Berber calendar year 911, Buddhist calendar year 505
  • Either a common year starting on Thursday, Friday or Saturday or a leap year starting on Thursday or Friday
  • Lucius Antonius surrenders to Octavian
  • Treaty of Brundisium: The treaty is cemented by the marriage of Mark Antony and Octavia, sister of Octavian
  • Athenodorus a philosopher, encounters a ghost in Athens
  • Parthians conquer Jerusalem
  • Births: the twins of Cleopatra VII of Egypt and Mark Antony

In Geography

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I-40 – a U.S. interstate connecting California to North Carolina

40 – National highways in Argentina, Canada, China, Czech Republic, Israel, Japan, Jordan, Mexico, South Korea, Saudi Arabia, Sweden, UK, and USA

40th Parallel South – crosses land in Australia, New Zealand, Chile, and Argentina

40th Parallel North – crosses land in Spain, Italy, Albania, Greece, Turkey, Armenia, Azerbaijan, Turkmenistan, Uzbekistan, Tajikistan, Kyrgyzstan, China, North Korea, Japan, USA, and Portugal

40th Meridian West – crosses Greenland, Brazil, and Antarctica

4oth Meridian East – crosses Russia, Ukraine, Turkey, Syria, Iraq, Saudi Arabia, Eritrea, Ethiopia, Kenya, Tanzania, Mozambique, and Antarctica

40-Step Stairway – historical place in Busan, South Korea

Forty Foot – a promontory on the southern tip of Dublin Bay, Ireland where people have been swimming in the Irish Sea all year round for hundreds of years

Forty Shades of Green is a visual term for rural Ireland

40 – the code for direct dial international phone calls to Romania

WD-40 – a popular penetrating oil whose name stands for the 40th formula of Water Displacement

Here’s #2 on the Billboard Charts from 40 years ago today – April 2, 1977 – our wedding day

On 40

Forty (40) offers a lot of significance, so there is no way to capture forty’s vast nature. Of course, I imagine John will include his share of military references (which I, and hopefully everyone, will appreciate).

Nonetheless, I dedicate this post to the members of my graduating class who recently came together to celebrate our 40 years since high school graduation.

In Mathematics

  • 40 is an octagonal number and a Stormer number
  • Adding up some of its divisors (1, 4, 5, 10 and 20) equals 40, 40 is a semiperfect number
  • To add hours and minutes easily, use 40. Example, to add 2 hr 40 min and 3 hr 30 min, use 240 + 330 + 40 = 610, therefore, 6 hr 10 min

In Science

  • The atomic number of zirconium, which has 40 protons, thus 40 electrons in its neutrally charge state
  • The planet Venus forms a pentagram in the night sky every eight years with it returning to its original point every 40 years with a 40 day
  • Messier object M40 is a magnitude 9.0 double star in the constellation Ursa Major
  • Counting from the woman’s last menstrual period.the number of weeks for an average term of pregnancy

In Religion
The number 40 is significant in the Abrahamic traditions  (some examples)


  • Rain fell for “40 days and 40 nights” during the flood
  • Spies explored the land of Israel for “40 days”
  • The Hebrew people lived in the Sinai desert for “40 years”
  • Several Jewish leaders and kings (Eli, Saul, David, Solomon) ruled for 40 years
  • Goliath challenged the Israelites twice a day for 40 days before David defeated him
  • Moses spent three consecutive periods of “40 days and 40 nights” on Mount Sinai
  • 40 lashes is one of the punishments issued by the Sanhedrin


  • Before the temptation of Christ, Jesus fasted “40 days and 40 nights”
  • Lent consists of the 40 days preceding Easter. However, Western Christianity excludes Sundays while Eastern Christianity includes Sundays
  • The period from the resurrection of Jesus to the ascension of Jesus is 40 days


  • Muhammad was 40 years old when he first received the revelation delivered by the archangel Gabriel
  • Prophet Ibrahim spent 40 days in a fire and lived because Allah made the fire like flowers
  • Prophet Yunus was in a whales mouth for 40 days
  • Muhammad was praying and fasting in the cave for 40 days
  • Muhammad had 40 followers to spread the religion of Islam
  • Mourning period officially last for 40 days

In Cultures

  • Some Russians believe that ghosts of the dead linger at the site of their death for 40 days
  • In Hinduism, some popular religious prayers consist of 40 shlokas or dohas (couplets, stanzas)
  • To understand a people, you must live among them for 40 days. (Arabic proverb), then again, others say “Life begins at 40″
  • The ruby wedding anniversary
  • The customary number of hours in a regular workweek in some Western countries

In Sports

  • Major League Baseball allows each team to have a 40-player roster with major-league contracts at any given time (not including players on the 60-day disabled list)
  • The 40 yard dash is an important metric in football (US) scouting.
  • The third point gained in a tennis game

Retired #40

  • In Major League Baseball: Don Wilson (Astros) and Danny Murtaugh (Pirates)
  • In the NBA: Bill Laimbeer (Pistons), Jason Collier (Hawks), and Byron Beck (Nuggets)
  • In the NFL: Gale Sayers (Bears), Mike Haynes. (Patriots), Tom Brookshier (Eagles), Joe Morrison (Giants), and Pat Tillman (Cardinals)

Old Rosebud won the 40th Kentucky Derby (1914)

NASCAR #40 has won 5 races, led by Sterling Marlin (4). Other drivers include Kenny Wallace, Robby Gordon, David Stremme, Jamie McMurray, Bobby Hamilton, and Dario Franchitti

Steelers defeated the Seahawks in Super Bowl XL

In US History

  • 40 acres and a mule refers to the short-lived policy, during the last stages of the American Civil War
  • The 40th United States Congress (1867-1869) during the third and fourth years of Andrew Johnson’s Presidency, which impeached President Johnson and completed the Alaska Purchase
  • President Ronald Reagan, the 40th US president
  • James K Polk’s slogan: Fifty-four Forty or Fight

In Geography

  • Interstate 40 links California to North Carolina
  • U.S. Route 40 links Baltimore, Maryland, to Park City, Utah, which generally parallels I-70
  • European route E40 links Calais and Ridder, A40  links London and Fishguard), and M40 links London and Birmingham.
  • The 40th parallel north crosses Europe, the Mediterranean Sea, Asia, the Pacific Ocean, North America, and the Atlantic Ocean.
  • The 40th parallel north serves as the boundary between Kansas and Nebraska
  • The 40th parallel south cross much more water than land (Argentina, Chile, Australia (Tasmania), and New Zealand)

In Entertainment

  • A song by Dave Matthews Band
  • A 1983 song by U2 from their album War
  • The radio program American Top 40
  • In The Early Show segment “Chef on a Shoestring”, chefs are given a $40 budget
  • $40 Rachel Ray’s budget for food per day when visiting a city in the show $40 a Day

In the Year 40 AD

  • A leap year starting on Friday
  • Roman Emporer Caligula starts on a campaign to conquer Britain, fails miserably, declares himself victorious, and then he appoints his horse, Incitatus, a senator
  • The Vietnamese Trung sisters rebel against the rule of the Chinese Emperor Guangwu of Han
  • Philosopher Philo teaches that all men are born free
  • Christianity comes to Egypt as a church in Alexandria
  • Mark the Evangelist founds the Coptic Orthodox Church as the first pope
  • An early Christian church erects in Corinth

In the Year 40 BC

  • Either a common year starting on Thursday, Friday or Saturday or a leap year starting on Thursday or Friday
  • Treaty of Brundisium: The Roman Republic divided into spheres of influence. Gaius Octavian takes control of the Western provinces while Mark Antony gets the Eastern provinces; The marriage of Antony and Octavia, sister of Octavian seals the treaty

Miscellaneous about Forty

  • The code for direct dial international phone calls to Romania
  • The caliber of the bullet in a number of firearms cartridges, most notably the .40 S&W
  • A great lubricant, WD-40, named after the 40 attempts it took to find this water displacement formula
  • Ali Baba and the 40 Thieves, who didn’t have this 40-ounce malt liquor available to them
  • 40 winks references sleep

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