180 (one hundred ndeighty) is the

natural number In mathematics, the natural numbers are those numbers used for counting (as in "there are ''six'' coins on the table") and ordering (as in "this is the ''third'' largest city in the country"). Numbers used for counting are called '' cardinal ...

following

179 Year 179 ( CLXXIX) was a common 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 Aurelius and Veru (or, less frequently, year 932 ''Ab urbe condit ...

and preceding

181 Year 181 ( CLXXXI) was a common year starting on Sunday (link will display the full calendar) of the Julian calendar. At the time, it was known as the Year of the Consulship of Aurelius and Burrus (or, less frequently, year 934 ''Ab urbe condit ...

In mathematics

180 is an

abundant number In number theory, an abundant number or excessive number is a number for which the sum of its proper divisors is greater than the number. The integer 12 is the first abundant number. Its proper divisors are 1, 2, 3, 4 and 6 for a total of 16. Th ...

, with its proper divisors summing up to 366. 180 is also a

highly composite number __FORCETOC__ A highly composite number is a positive integer with more divisors than any smaller positive integer has. The related concept of largely composite number refers to a positive integer which has at least as many divisors as any smaller ...

, a positive integer with more divisors than any smaller positive integer. One of the consequences of 180 having so many divisors is that it is a

practical number In number theory, a practical number or panarithmic number is a positive integer n such that all smaller positive integers can be represented as sums of distinct divisors of n. For example, 12 is a practical number because all the numbers from 1 ...

, meaning that any positive number smaller than 180 that is not a divisor of 180 can be expressed as the sum of some of 180's divisors. 180 is a Harshad number and a

refactorable number A refactorable number or tau number is an integer ''n'' that is divisible by the count of its divisors, or to put it algebraically, ''n'' is such that \tau(n)\mid n. The first few refactorable numbers are listed in as : 1, 2, 8, 9, 12, 18, ...

. 180 is the sum of two

square number In mathematics, a square number or perfect square is an integer that is the square of an integer; in other words, it is the product of some integer with itself. For example, 9 is a square number, since it equals and can be written as . The u ...

s: 12² + 6². It can be expressed as either the sum of six consecutive

prime number A prime number (or a prime) is a natural number greater than 1 that is not a Product (mathematics), product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime ...

s: 19 + 23 + 29 + 31 + 37 + 41, or the sum of eight consecutive

s: 11 + 13 + 17 + 19 + 23 + 29 + 31 + 37. 180 is an

Ulam number In mathematics, the Ulam numbers comprise an integer sequence devised by and named after Stanislaw Ulam, who introduced it in 1964. The standard Ulam sequence (the (1, 2)-Ulam sequence) starts with ''U''1 = 1 and ''U''2 =&nb ...

, which can be expressed as a sum of earlier terms in the Ulam sequence only as 177 + 3. 180 is a 61- gonal number. Half a

circle A circle is a shape consisting of all points in a plane that are at a given distance from a given point, the centre. Equivalently, it is the curve traced out by a point that moves in a plane so that its distance from a given point is cons ...

has 180 degrees, and thus a

U-turn A U-turn in driving refers to performing a 180° rotation to reverse the direction of travel. It is called a "U-turn" because the maneuver looks like the letter U. In some areas, the maneuver is illegal, while in others, it is treated as a ...

is also referred to as a ''180''. Summing

Euler's totient function In number theory, Euler's totient function counts the positive integers up to a given integer that are relatively prime to . It is written using the Greek letter phi as \varphi(n) or \phi(n), and may also be called Euler's phi function. In ...

φ(''x'') over the first + 24 integers gives 180. In binary it is a digitally balanced number, since its binary representation has the same number of zeros as ones (10110100).

In religion

The

Book of Genesis The Book of Genesis (from Greek ; Hebrew: בְּרֵאשִׁית ''Bəreʾšīt'', "In hebeginning") is the first book of the Hebrew Bible and the Christian Old Testament. Its Hebrew name is the same as its first word, ( "In the beginning" ...

says that

Isaac Isaac; grc, Ἰσαάκ, Isaák; ar, إسحٰق/إسحاق, Isḥāq; am, ይስሐቅ is one of the three patriarchs of the Israelites and an important figure in the Abrahamic religions, including Judaism, Christianity, and Islam. He was ...

died at the age of 180.

Other

* All of the ''

Final Destination ''Final Destination'' is an American horror franchise that includes five films, two comic books, and nine novels. It is based on an unproduced spec script by Jeffrey Reddick, originally written for ''The X-Files'' television series, and was ...

'' series has used the number for death clues, starting off in the first film as a flight number to a 747 airliner based on

TWA Flight 800 Trans World Airlines Flight 800 (TWA800) was a Boeing 747-100 that exploded and crashed into the Atlantic Ocean near East Moriches, New York, on July 17, 1996, at about 8:31pm. EDT, 12 minutes after takeoff from John F. Kennedy International ...

. * 180 is the highest score possible with three darts.

References

External links

* * {{DEFAULTSORT:180 (Number) Integers

In mathematics

In religion

Other

See also

References

External links