60 (number)

From Wikipedia, the free encyclopedia

60 (sixty) is the natural number following 59 and preceding 61. Being thrice twenty, 60 is called "three score" in some older literature.

0 10 20 30 40 50 60 70 80 90

Cardinal 60
sixty
Ordinal 60th
sixtieth
Numeral system sexagesimal
Factorization 2^2 \cdot 3 \cdot 5
Divisors 1, 2, 3, 4, 5, 6,
10, 12, 15, 20, 30, 60
Roman numeral LX
Roman numeral (Unicode) LX, lx
Binary 111100
Octal 74
Duodecimal 50
Hexadecimal 3C
Gematria ס (Samekh)
Look up sixty in
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Contents

[edit] In 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. Being ten times a perfect number, 60 is a semiperfect 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). 60 is the smallest number with exactly 12 divisors.

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). It is adjacent to two prime numbers (59,61).

The smallest non-abelian simple group has order 60.

In geometry, 60 is the number of seconds in a minute, and the number of minutes in a degree. In normal space, the 3 interior angles of an equilateral triangle each measure 60 degrees, adding up to 180 degrees.

The Babylonian number system had a base of sixty. The number system in the Mali Empire was apparently also based on sixty (this is reflected in the counting system of the Maasina Fulfulde, a variant of the Fula language spoken in contemporary Mali). A number system with base-sixty is called the sexagesimal (original meaning of sexagesimal is sixtieth).

The sexagenary cycle plays a role in Chinese calendar and numerology. (Originally, sexagenary means sixty each, also centenary means one hundred each.)

Because 60 is divisible by the sum of its digits in base 10, it is a Harshad number.

In German: das Schock and in Latin: sexagena equals 60 = 5 dozen = 1/2 small gross. This quantity was used in international medieval treaties e.g. for ransom of captured Teutonic Knights.

[edit] In science

  • The atomic number of neodymium, a lanthanide. The neodymium following element with the ordinal number 61 (promethium) has in contrast to the neighbour elements no stable isotopes.

[edit] Astronomy

[edit] In religion

  • Judaism
    • In the laws of kashrut, the proportion (60:1) of kosher to non-kosher ingredients which can render an admixture kosher post-facto. (Talmud, Tractate Chullin 98b ; Shulchan Aruch, Yoreh Deah 98)
    • In the Bedtime Shema, the number of strong men (giborim) said to surround King Solomon's bed.

[edit] In other fields

Sixty is:

[edit] In music

[edit] In sports

[edit] Historical years

60 A.D., 60 B.C., 1960, 2060, etc.

[edit] References

  1. ^ Dennis Guedj, Numbers: The Universal Language, transl. Lory Frankel. New York: Harry N. Abrams, Inc. Publishers (1997): 71. "60: the ace of divisibility. The more divisible a number is ... the more useful it proves in certain situations. ... Is it because 60 is highly divisible that the hour has been divided into 60 minutes, and the minute into 60 seconds? Look at the list of its twelve divisors ... Compare this with the larger number 100, which has only nine divisors."