85 (number)

85 is the natural number following 84 and preceding 86.

In mathematics

Eighty-five is an octahedral number, a centered triangular number, a centered square number, a decagonal number, and a Smith number.

85 can be expressed as a sum of two squares in two ways, 85= 9² + 2² = 7² + 6²

In astronomy

• Messier object M85, a magnitude 10.5 lenticular galaxy in the constellation Coma Berenices
• The New General Catalogue object NGC 85, a galaxy in the constellation Andromeda
• The Saros number of the solar eclipse series which began on -170 March 14 and ended on 1110 April 20. The duration of Saros series 85 was 1280.1 years, and it contained 72 solar eclipses. Further, the Saros number of the lunar eclipse series which began on -103 August 2 and ended on 1267 November 3. The duration of Saros series 85 was 1370.3 years, and it contained 77 lunar eclipses.

In other fields

Eighty-five is also:

• The atomic number of astatine
• The model number of SU-85
• The number of the French department Vendée
• The designation of Interstate 85, a freeway that runs from Alabama to Virginia; the European route E85 from Klaipéda to Alexandropoúli
• The ISBN Group Identifier for books published in Brazil
• The title of a webcomic novel created by Gemma Bright and Tammy Holliday.
• The year AD 85, 85 BC, or 1985.