60 (number)
60 is the natural number following 59 and preceding 61.
Mathematics
Sixty is a composite number with divisors 1, 2, 3, 4, 5, 6, 10, 12, 15, 20, 30, making it also a highly composite number. Because 60 is the sum of its unitary divisors (excluding itself), it is a unitary perfect number. And because it is divisible by the sum of its digits in base 10, it is a Harshad number. 60 is the smallest number divisible by the numbers 1 to 6. (There is no smaller number divisible by the numbers 1 to 5).
This number is the sum of a pair of twin primes (29 + 31), as well as the sum of four consecutive primes (11 + 13 + 17 + 19).
The smallest non-abelian simple group has order 60.
In normal space, the interior angles of an equilateral triangle each measures 60 degrees, adding up to 180 degrees.
The Babylonian number system had a base of sixty. A number system with base sixty is called a sexagesimal number system.
The Sexigesimal cycle plays a role in Chinese numbering and numerology.
Other fields
Sixty is also:
- the atomic number of neodymium, a lanthanide.
- in the measurement of time, the number of seconds in a minute, and the number of minutes in an hour.
- in geometry, the number of seconds in a minute, and the number of minutes in a degree.
- a common speed limit, in miles per hour, for freeways in many US states.
- in years of marriage, the diamond wedding anniversary.
- the maximum number of marbles (game pieces) in Chinese checkers.
- the code for international direct dial calls to Malaysia.
- The year AD 60, 60 BC, or 1960.
