180 (number)

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180 (one hundred eighty in American English, one hundred and eighty in British English) is the natural number following 179 and preceding 181.

List of numbers — Integers

<< 180 181 182 183 184 185 186 187 188 189 >>
Cardinal One hundred [and]
eighty
Ordinal 180th
Factorization 2^2 \cdot 3^2 \cdot 5
Divisors 1, 2, 3, 4, 5, 6, 9, 10, 12, 15, 18,
20, 30, 36, 45, 60, 90, 180
Roman numeral CLXXX
Binary 10110100
Duodecimal 130
Hexadecimal B4
Vigesimal 90

[edit] In mathematics

One hundred [and] eighty is the sum of six consecutive primes (19 + 23 + 29 + 31 + 37 + 41), as well as the sum of eight consecutive primes (11 + 13 + 17 + 19 + 23 + 29 + 31 + 37).

The sum of Euler's totient function φ(x) over the first twenty-four integers is 180. Since 180 is divisible by the total number of its divisors, it is a refactorable number.

Using degrees (°) to measure angles, 180° is called straight angle, and makes a semicircle. 180° is equivalent to π rads. In normal space, the interior angles of a triangle add up to 180°.

180 is a Harshad number in base 10.

[edit] In other fields

  • 180° also means antipode. For example, a "180-degree change" indicates a radical change.
  • The maximum possible score in one turn at darts (three treble 20s).
  • 180 (computer game) - A darts computer game released for various home computers in 1986.
  • In astronomy, when two planets are 180 degrees apart, they are said to be in opposition. In astrology, this is an aspect that is considered to be negative in influence.
  • The year AD 180 or 180 BC.
  • A trick in many extreme sports where a rider rotates through half a turn and lands, now rolling backwards.
  • A 180 is the highest possible score on the Law School Application Test, LSAT.
  • 180 (drink), an energy drink
  • 180° is the spread or difference between the freezing point & boiling point of water on the Fahrenheit scale