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{{Infobox number | |||
| number = 84 | |||
| divisor = 1, 2, 3, 4, 6, 7, 12, 14, 21, 28, 42, 84 | |||
}} | |||
'''84''' ('''eighty-four''') is the [[natural number]] following [[83 (number)|83]] and preceding [[85 (number)|85]]. | |||
== In mathematics == | |||
[[File:Hepteract ortho petrie.svg|thumb|200px|left|A [[hepteract]] is a seven-[[dimension]]al [[hypercube]] with 84 [[penteract]] 5-faces]] | |||
84 is the sum of the first seven [[triangular number]]s (making it a [[tetrahedral number]]), as well as the sum of a [[twin prime]] (41 + 43). Being thrice a perfect number, 84 is itself a [[semiperfect number]]. | |||
84 is the [[lim sup]] of the largest finite subgroup of the [[mapping class group]] of a [[genus]] <math>g</math> surface divided by <math>g</math>. | |||
A [[hepteract]] is a seven-[[dimension]]al [[hypercube]] with 84 [[penteract]] 5-faces. | |||
== In astronomy == | |||
*[[Messier object]] [[Messier 84|M84]], a [[visual magnitude|magnitude]] 11.0 [[lenticular galaxy]] in the [[constellation]] [[Virgo (constellation)|Virgo]] | |||
*The [[New General Catalogue]] [http://www.ngcic.org/ object] [[NGC 84]], a single star in the constellation [[Andromeda (constellation)|Andromeda]] | |||
*The [[Saros cycle|Saros]] number of the [[solar eclipse]] series which began on -181 April 14 and ended on 1099 May 22. The duration of Saros series 84 was 1280.1 years, and it contained 72 solar eclipses.<ref>http://eclipse.gsfc.nasa.gov/SEsaros/SEsaros084.html</ref> Further, the number of the [[lunar eclipse]] series which began on -96 September 13 and ended on 1401 February 28. The duration of Saros series 84 was 1496.5 years, and it contained 84 lunar eclipses.<ref>http://eclipse.gsfc.nasa.gov/LEsaros/LEsaros084.html</ref> | |||
==In sports== | |||
[[Los Angeles Lakers]] [[Magic Johnson]] holds the record for assists in a 6-game NBA Finals Series (1985) with 84 | |||
== In other fields == | |||
[[Image:LocationVietnam.png|thumb|90px|[[code for international direct dial|dial +84]] for [[Vietnam]]]] | |||
'''Eighty-four''' is also: | |||
* The year AD '''84''', [[84 BC]], or 1984. | |||
* The [[atomic number]] of [[polonium]] | |||
* The model number of [[Harpoon missile]] | |||
* [[WGS 84]] - The latest revision of the [[World Geodetic System]], a fixed global reference frame for the Earth. | |||
* The house number of [[84 Avenue Foch]] | |||
* The number of the French department [[Vaucluse]] | |||
* The designation of [[Interstate 84 (disambiguation)|Interstate 84]], two [[Interstate Highways]] that run from [[Oregon]] to [[Utah]] and from [[Pennsylvania]] to [[Massachusetts]]. | |||
* The [[code for international direct dial]] phone calls to [[Vietnam]] | |||
* The town of [[Eighty Four, Pennsylvania|Eighty Four]], [[Pennsylvania]] | |||
* The company [[84 Lumber]] | |||
* The [[ISBN]] Group Identifier for books published in [[Spain]] | |||
* A variation of the [[game]] [[42 (dominoes)|42]] played with two sets of [[dominoes]]. | |||
* The film "[[84 Charing Cross Road]]" (1987) starring [[Anne Bancroft]] and [[Anthony Hopkins]] | |||
* [[KKNX]] Radio 84 in [[Eugene, Oregon]] | |||
* ''[[The John Larroquette Show]]'' ran on [[NBC]] from 1993 to 1996 for 84 episodes | |||
* The B-Side to [[Up All Night (Take That song)|"Up All Night" (Take That song)]] | |||
* British Army term for the 84mm [[Carl Gustav recoilless rifle]]. | |||
* How many years it takes [[Uranus]] to orbit the sun once | |||
==References== | |||
{{reflist}} | |||
{{Integers|zero}} | |||
[[Category:Integers]] | |||
Revision as of 01:06, 25 January 2014
Template:Infobox number 84 (eighty-four) is the natural number following 83 and preceding 85.
In mathematics
84 is the sum of the first seven triangular numbers (making it a tetrahedral number), as well as the sum of a twin prime (41 + 43). Being thrice a perfect number, 84 is itself a semiperfect number.
84 is the lim sup of the largest finite subgroup of the mapping class group of a genus surface divided by .
A hepteract is a seven-dimensional hypercube with 84 penteract 5-faces.
In astronomy
- Messier object M84, a magnitude 11.0 lenticular galaxy in the constellation Virgo
- The New General Catalogue object NGC 84, a single star in the constellation Andromeda
- The Saros number of the solar eclipse series which began on -181 April 14 and ended on 1099 May 22. The duration of Saros series 84 was 1280.1 years, and it contained 72 solar eclipses.[1] Further, the number of the lunar eclipse series which began on -96 September 13 and ended on 1401 February 28. The duration of Saros series 84 was 1496.5 years, and it contained 84 lunar eclipses.[2]
In sports
Los Angeles Lakers Magic Johnson holds the record for assists in a 6-game NBA Finals Series (1985) with 84
In other fields
Eighty-four is also:
- The year AD 84, 84 BC, or 1984.
- The atomic number of polonium
- The model number of Harpoon missile
- WGS 84 - The latest revision of the World Geodetic System, a fixed global reference frame for the Earth.
- The house number of 84 Avenue Foch
- The number of the French department Vaucluse
- The designation of Interstate 84, two Interstate Highways that run from Oregon to Utah and from Pennsylvania to Massachusetts.
- The code for international direct dial phone calls to Vietnam
- The town of Eighty Four, Pennsylvania
- The company 84 Lumber
- The ISBN Group Identifier for books published in Spain
- A variation of the game 42 played with two sets of dominoes.
- The film "84 Charing Cross Road" (1987) starring Anne Bancroft and Anthony Hopkins
- KKNX Radio 84 in Eugene, Oregon
- The John Larroquette Show ran on NBC from 1993 to 1996 for 84 episodes
- The B-Side to "Up All Night" (Take That song)
- British Army term for the 84mm Carl Gustav recoilless rifle.
- How many years it takes Uranus to orbit the sun once
References
43 year old Petroleum Engineer Harry from Deep River, usually spends time with hobbies and interests like renting movies, property developers in singapore new condominium and vehicle racing. Constantly enjoys going to destinations like Camino Real de Tierra Adentro.