A page of the Numeropedia - the Special Encyclopedia of Numbers
[Astronomy] The number of all Apollo missions: Apollo 1 (on 27 January 1967), Apollo 7 to 17. In which, the last 7 missions, Apollo 11 to 17, are for Lunar Landing: 6 successful missions and 1 failed: Apollo 13.
[Astronomy] The nautical twilight is when the center of the (refracted) Sun is 12o below the horizon.
[Biology] The number of pair of ribs on a human skeleton (24 ribs totally).
[Chemistry] The atomic number of Magnesium (Mg).
[Education] The number of graded classes/levels a student must attend after kindergarten to high school graduate.
[EECS] In hexadecimal number system, C = 12.
[EECS] 12(W, KW or MW) is one of standard numerical values for resistors (of tolerance class 5%). 12pf (picofarads) is one of standard numerical values for capacitors.
[Flag] The number of stars forming a circle on the middle of the European Union flag, representing the first 12 nations (when the Union was founded on 1 November 1993): Belgium, Denmark, France, Germany, Greece, Ireland, Italy, Luxemburg, Netherlands, Portugal, Spain and United Kingdom. The newest 3 members since 1 January 1995 are: Austria, Finland and Sweden.
[Flag] The number of white triangular rays encircling the white sun in the dark blue rectangle on the national flag of Taiwan.
[Flag] The number of white stars (in 3 horizontal lines of 3, 4 and 5 stars next to a white crescent) in the top blue band of the national flag of Uzbekistan.
[Flag] The national flag of Nauru features a white 12-pointed star (below the yellow narrow horizontal central strip, indicates the country’s location in relation to the Equator), representing its 12 original tribes.
[Flag] The number of triangular sunrays radiated from a yellow sun in the blue triangle at the upper left corner of the national flag of Namibia.
[Game] The number of letters (and spaces) available on the current version puzzle-board of the “Wheel of Fortune” TV show: 12 each on the top row and the bottom row and 14 each on the middle 2 rows.
[Geology] The number of countries that the Equator runs though: Ecuador, Peru, Colombia, Venezuela, Brazil, Gabon, Congo, Zaire, Tanzania, Uganda, Kenya, Indonesia.
[Language] Prefixes: Duode-, Duodec-, Dodec-, Dodeca-…
[Language] The number of letters in the Hawaiian alphabet: A, E, H, I, K, L, M, N, O, P, U and W; 5 vowels (A, E, I, O and U) and 7 consonants (H, K, L, M, N, P and W).
[Language] The number of words in the city of Los Angles’ full name: “El Pueblo de Nuestra Senora la Reina de los Angeles de Porciuncula, a total of 65 letters and spaces. It is usually abbreviated to only L.A.
[Language] Tween (or pre-teen) refers to a child between middle childhood and adolesence, generally in the age range of 8 to 12 years old.
[Language] The number of letters in the Rotokas alphabet (a language spoken in the Bougainville Island in South Pacific Ocean): A, E, G, I, K, O, P, R, S, T, U and V.
[Library] ISBN-0-12 is the International Standard Book Number for books published by Academic Press (or Morgan Kaufmann).
[Movie] Names of TV shows/series or movies: “12 Angry Men”, “12 Monkeys”, “Twelfth Night”, “Twelve O’clock High”, “Adam-12”,“Twelve and Holding”, 12 Days of Christmas Eve” and “Cheaper by the Dozen”.
Also “Ocean’s Eleven” and its sequels “Ocean’s Twelve” and “Ocean’s Thirteen”.
[Music] The number of basic musical tones within one octave: A --> A+/B- --> B --> C --> C+/D- --> D --> D+/E- --> E --> F --> F+/G- --> G --> G+/A- --> A (higher). The frequency ratio of 2 adjacent musical tones is 21/12 (i.e. the twelfth root of 2). Hence the frequency ratios between 2 adjacent musical notes are either 21/12 (for C/B and F/E) or 22/12 = 21/6 (for others, e.g., B/A or D/C…).
[Phone] The number of basic keys on a telephone keypad: 10 keys from 0-9, the “*” key and the “#” key.
[Theology] The number of Apostles chosen by Jesus Christ: Simon (renamed Peter), Andrew, James the Elder (or the Greater), John, Philip of Bethsaida, Bartholomew, Matthew, Thomas, James the Younger (or the Less, the Little), Jude (or Judas, Thaddaeus), Simon the Cananaean and Judas Iscariot. Others: Matthias was chosen by the 11 Apostles to replace Judas Iscariot, who betrayed Jesus for 30 silver coins and later repented and hanged himself. Paul of Tarsus (originally named Saul) is called an Apostle and respected as the others.
[Trivia] New York’s Wall Street got its name from a 1340-foot long and 12-foot-tall wall.
[Trivia] The 12th wedding anniversary is traditionally named silk (or fine linen) anniversary. Modernly, it may be replaced by pearls (or jade).
[Trivia] Pack of soft drink cans or bottles: 4, 6, 12, 18, 20, 24, 30 or 36.
[Trivia] The number of eggs in a carton: 6, 12, 18 or 36.
[World] The number of original members of the NATO (North Atlantic Treaty Organization), founded in 1949: Belgium, Canada, Denmark, France, Iceland, Italy, Luxembourg, Netherlands, Norway, Portugal, the United Kingdom and the U.S. As of 2005, the number is 26.
[World] The number of Olympian gods and goddesses in Greek mythology, who ruled the universe from atop Greece’s Mount Olympus: Aphrodite (Venus), Apollo, Ares (Mars), Artemis (Diana), Athena (Minerva), Hades (Pluto), Hermes (Mercury), Hera (Juno), Hephaestus (Vulcan or Mulciber), Hestia (Vesta), Poseidon (Neptune) and Zeus (Jupiter). Sometimes, the list includes 2 more names: Demeter (Ceres) and Dionysus (Bacchus). Roman names are in parentheses.
[World] The ISO country code for Algeria is 012. (ISO-3166)
[Sport] A “magic” number 2.375 appears in the NFL (National Football League) quarterback rating formula: 100×(2.375×4)/6 = 158.33, computing points from 4 categories: percentage of completions (maximum 2.375 if ≥ 77.5%), average yards gained per attempt (maximum 2.375 if ≥ 12.5 yards), percentage of touchdown passes (maximum 2.375 if ≥ 11.875%) and percentage of interceptions (maximum 2.375, minimum 0 if it is ≥ 9.5%). The perfect rating score is 158.33.