- "Twenty" redirects here. For the village in
England, see Twenty, Lincolnshire.
) is the natural number
and preceding 21
A group of twenty units may also be referred to as a
- An icosahedron has 20 faces. A
dodecahedron has 20 vertices.
- 20 can be written as the sum of three Fibonacci Numbers uniquely, i.e. 20 = 13 +
5 + 2.
- The product of the number of divisors
and the number of proper divisors of 20 is exactly 20.
- The number of proteinogenic
amino acids that are encoded by the
standard genetic code.
- In some countries, the number 20 is used as an index in
measuring visual acuity. 20/20
indicates normal vision at 20 feet, although it is commonly used to
mean "perfect vision" (Note that this applies only to countries
using the Imperial system. The metric
equivalent is 6/6). When someone is able to see only after an event
how things turned out, that person is often said to have had "20/20
- There are 20 baby teeth in the deciduous dentition.
is the age of majority in Japanese
tradition. Someone who is exactly twenty years old is
described as hatachi
- The age to be a adult in some cultures.
In other fields
- The number of twenty can also be called a score (as Abraham Lincoln did in his Gettysburg Address).
- Twenty questions is a popular
- The Twenty Year Curse refers
to the pattern of presidents of the United
States who were elected to office in 1840,
1860, 1880, 1900, 1920, 1940, and 1960 to die in office.
This pattern ended with the 1980 presidency of
Reagan, who survived his time in
office and, notably, an attempted assassination.
- Bands with the number twenty in their name include Matchbox Twenty
- In the 1974 sci-fi film Dark
Star, Exponential Thermostellar
Bomb number 20 threatens to detonate in the Dark
Star's bomb bay
- A 20-minute-long program of advertisements and trailers shown
before some films playing in American movie theaters is called
"The Twenty" (spelled "The 20wenty")
- Yan Tan Tethera is a 20-word
jingle for counting sheep
- The ordinal adjective is vicenary
- 20/20 is a late-night
newsmagazine program on the ABC network, that has been
hosted by Barbara Walters, Hugh Downs, Elizabeth
Vargas, and others
- In the roleplaying game Dungeons and Dragons (as well as other
RPGs that use twenty-sided dice), twenty-sided dice play a pivotal
role in gameplay, and to "roll a twenty" is significant to the
point that it is sometimes used in other, usually related,
contexts, similar to the use of "doubles" in reference to Monopoly.
- Cigarettes are usually packaged with
20 in each pack.
- "T" is the 20th letter in the alphabet.
- According to The Strokes in the song
You Only Live Once there
are 20 ways to see the world, and 20 ways to start a fight.
- Twenty, a village in
- In the United States
Constitution, $20 is the threshold value of civil disputes
above which the right to trial by jury is preserved
- A denomination of U.S.
dollar featuring Andrew Jackson's
- A denomination of Pound sterling
featuring Adam Smith's portrait
international direct dial phone calls to Egypt
designation of Interstate 20, a
freeway that runs from Texas to South Carolina
- 20 , a 1988 album by Harry Connick, Jr.
- Twenty , a 1997 album by Lynyrd Skynyrd
- 20 , a 2007 album by Terminaator
- Twenty , a 2006 concert celebrating the
20th Anniversary of Regine
Velasquez held at the Araneta Coliseum, Philippines.
It was awarded Best Major Concert Act by the Aliw
- CB slang for "a place", being short for
"10-20", used in reference to a person or object's location
- One of the TCP/IP "well-known ports", port 20
being used for File Transfer
- In the French and Portuguese education system, grades are given
out of 20. Giving 20/20 is a very rare occasion.