180 number: Encyclopedia - 180 number

180 (number)

180 (one hundred eighty) is the natural number following 179 and preceding 181.

List of numbers -- Integers

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180 number - In mathematics

One hundred 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).

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.

180 number - In other fields

• 180° also means antipode. For example, a "180-degree change" indicates a radical change.
• Interstate 180, the designation of some spur routes of Interstate 80.
• The maximum possible score in one turn at darts.
• 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.

180 number - Other numbers in the 180s

181 = prime number, Chen prime, palindromic prime, star number, centered square number, centered pentagonal number, sum of five consecutive primes (29 + 31 + 37 + 41 + 43)

182 = 2 7 13, sphenic number, pronic number, nontotient

183 = 3 61

184 = 2^3 23, sum of four consecutive primes (41 + 43 + 47 + 53)

185, see 185 (number)

186 = 2 3 31, sphenic number, nontotient

187 = 11 17, sum of three consecutive primes (59 + 61 + 67), sum of nine consecutive primes (7 + 11 + 13 + 17 + 19 + 23 + 29 + 31 + 37), self number

188 = 2^2 47, nontotient, untouchable number

189 = 3^3 7 = 6³+(-3)³ = 4³+5³, centered cube number

Categories: Integers | Darts

Adapted from the Wikipedia article "180 number", under the G.N U Free Docmentation License. Please also see http://en.wikipedia.org/wiki