Twenty-eight or 28 may refer to:
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28 (number)
28 (twenty-eight) is the natural number following 27 and preceding 29.
In mathematics
It is a composite number, its proper divisors being 1, 2, 4, 7, and 14.
Twenty-eight is the second perfect number - it is the sum of its proper diviso ...
, the natural number following 27 and preceding 29
* one of the years
28 BC
__NOTOC__
Year 28 BC was either a common year starting on Saturday, Sunday or Monday or a leap year starting on Saturday or Sunday (link will display the full calendar) of the Julian calendar (the sources differ, see leap year error for further ...
,
AD 28
AD 28 ( XXVIII) was a leap year starting on Thursday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Silanus and Nerva (or, less frequently, year 781 ''Ab urbe condita''). ...
,
1928
Events January
* January – British bacteriologist Frederick Griffith reports the results of Griffith's experiment, indirectly proving the existence of DNA.
* January 1 – Eastern Bloc emigration and defection: Boris Bazhanov, J ...
,
2028
Predicted and scheduled events
* January 1 – Books, films, and other works published in 1932 will enter the public domain in the United States.
* January 12 – Partial lunar eclipse.
* January 26 – Small annular solar eclip ...
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''28'' (album), a 2005 electronic music album by Aoki Takamasa and Tujiko Noriko
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''28'' (book), a 2007 non-fiction book by Stephanie Nolen
*
''28'' (2014 film), a Sri Lankan feature drama
*
''28'' (2019 film), an Indian Malayalam-language film
*
Twenty-eight (card game)
Twenty-eight is an Indian trick-taking card game for four players, in which the Jack and the nine are the highest cards in every suit, followed by ace and ten. It thought to be descended from the game 304, along with similar Indian games known as ...
, an Indian trick-taking game for four players
* Twenty-eight, a nickname for the subspecies (''Barnardius zonarius semitorquatus'') of the
Australian ringneck
The Australian ringneck (''Barnardius zonarius'') is a parrot native to Australia. Except for extreme tropical and highland areas, the species has adapted to all conditions. Treatments of genus ''Barnardius'' have previously recognised two sp ...
* "Twenty Eight", a song by Karma to Burn from the album ''
Wild, Wonderful Purgatory
''Wild, Wonderful Purgatory'' is the second studio album by stoner rock band Karma to Burn. The album was released on May 31, 1999 (Europe) by Roadrunner UK, and July 7, 1999 (North America) by MIA Records. The album was reissued on March 18, 20 ...
'', 1999
*
Toyota-28, a boat made by Toyota and Yanmar
* "28", a song by Agust D from ''
D-2'' mixtape
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