21 number: Encyclopedia - 21 number

21 (number)

21 (twenty-one) is the natural number following 20 and preceding 22.

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List of numbers -- Integers

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21 number - In sports

Great twenty-ones include Mike Eruzione of the 1980 Men's Gold Olympic Hockey Team, Roberto Clemente, Hall-of-Famer of the Pittsburgh Pirates and Peter Forsberg, a great hockey player for the Quebec Nordiques, Colorado Avalanche and now Philadelphia Flyers and a future Hall-of-Famer.

Rising representatives of the great number of twenty-one include Bailey Buran (basketball, track & field, volleyball) and Liza Kane-Hartnett (volleyball, basketball, softball), athletes, Florida

21 number - In mathematics

Twenty-one is a Fibonacci number, a Harshad number, a Motzkin number, a triangular number and an octagonal number, as well as a composite number, its proper divisors being 1, 3 and 7.

21 appears in the Padovan sequence, preceded by the terms 9, 12, 16 (it is the sum of the first two of these).

21 number - In science

• The atomic number of scandium

In astronomy,

21 number - In human affairs: age 21

21 had been the age of majority in England and Wales before that age was lowered to 18 with the coming into force, on 1 January 1970, of the Family Law Reform Act 1969.

In the United States, 21 is the minimum legal age requred to drink alcohol. It is also the age at which it is legal to gamble and have sex with a prostitute in Nevada. In most states, a person who is 21 or over may also rent a car. 21 was the age for voting in the majority of states until the introduction of the Twenty-sixth Amendment.

21 number - In other fields

The current century -- spanning the years from 2001 to 2100 -- is referred to as the 21st century. This inspired many forward-looking 20th century events, company, and product names, like the Century 21 Exposition (another name for the 1962 Seattle World's Fair), Century 21 Real Estate, and Century 21 Television (producers of Sylvia and Gerry Anderson Supermarionation shows like Thunderbirds and Captain Scarlet).

The Twenty-first Amendment repealed the Eighteenth Amendment, thereby ending Prohibition.

Pier21 was, from 1928 to 1971, the place where immigrants entered Canada. It was called the "Gateway to Canada".

Twenty-one is:

• The number of spots on a standard cubical die (1+2+3+4+5+6).
• The number of firings in a gun salute to Royalty or leaders of countries.
• A card game, also called vingt-et-un (French for "twenty-one"), pontoon, or blackjack.
• A drinking game in which the goal is to get the group to 21 without saying it oneself.
• The title of a TV quiz show that ran from 1956 to 1958, most remembered for the scandal that the wins were fixed (see Quiz show scandals). It was remade in 2000.
• The title of at least three different movies:
  • A 1918 comedy starring Bryant Washburn and Gertrude Selby
  • A 1923 drama starring Richard Barthelmess and Dorothy Mackaill
  • A 1991 drama starring Patsy Kensit
• in the title of the TV show 21 Jump Street, starring Johnny Depp
• the standard TCP/IP port number for FTP connection.
• Twenty-One Demands were a set of demands which were sent to the Chinese government by the Japanese government of Okuma Shigenobu in 1915.
• Number 21, the plane flown by Gustave Whitehead
• Historical years: 21 A.D., 21 B.C., or 1921
• The title of a song by the Cranberries
• 21 is the title of a novel by Patrick O'Brian
• A street variation on basketball in which each player, of which there can be any number, plays for himself only (i.e. not part of a team); the name comes from the requisite number of baskets.
• The 21 Club is a top restaurant in New York City.
• In Israel, the number is associated with the profile 21 (the military profile designation granting an exemption from the military service).
• 21 grams is the weight of the soul, according to research by Duncan MacDougall, generally regarded as meaningless
• 21 Grams is the title of a movie, in reference to MacDougall's result (although this plays no direct role in the film)

Category: Integers

Adapted from the Wikipedia article "21 number", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki