10

This article is about the number. For the years, see 10 BC and AD 10. For other uses, see 10 (disambiguation).

"10th" redirects here. For other uses, see Tenth (disambiguation).

10 (ten) is the even natural number following 9 and preceding 11. Ten is the base of the decimal numeral system, the most common system of denoting numbers in both spoken and written language.

← 9 10 11 →
← 10 11 12 13 14 15 16 17 18 19 → List of numbers Integers ← 0 10 20 30 40 50 60 70 80 90 →
Cardinal	ten
Ordinal	10th (tenth)
Numeral system	decimal
Factorization	2 × 5
Divisors	1, 2, 5, 10
Greek numeral	Ι´
Roman numeral	X
Roman numeral (unicode)	X, x
Greek prefix	deca-/deka-
Latin prefix	deci-
Binary	10102
Ternary	1013
Senary	146
Octal	128
Duodecimal	A12
Hexadecimal	A16
Chinese numeral	十，拾
Hebrew	י (Yod)
Khmer	១០
Armenian	Ժ
Tamil	௰
Thai	๑๐
Devanāgarī	१०
Bengali	১০
Arabic & Kurdish & Iranian	١٠
Malayalam	൰
Egyptian hieroglyph	𓎆
Babylonian numeral	𒌋

Linguistics

• A collection of ten items (most often ten years) is called a decade.
• The ordinal adjective is decimal; the distributive adjective is denary.
• Increasing a quantity by one order of magnitude is most widely understood to mean multiplying the quantity by ten.
• To reduce something by one tenth is to decimate. (In ancient Rome, the killing of one in ten soldiers in a cohort was the punishment for cowardice or mutiny; or, one-tenth of the able-bodied men in a village as a form of retribution, thus causing a labor shortage and threat of starvation in agrarian societies.)

Mathematics

Ten is the smallest noncototient number. There are exactly 10 small Pisot numbers that do not exceed the golden ratio.

Decagon

Main article: Decagon

A ten sided polygon is called a decagon.

Science

The SI prefix for 10 is "deca-".

The meaning "10" is part of the following terms:

• decapoda, an order of crustaceans with ten feet.
• decane, a hydrocarbon with 10 carbon atoms.

10 is:

• The atomic number of neon.
• The number of hydrogen atoms in butane, a hydrocarbon.
• The number of spacetime dimensions in some superstring theories.

The metric system is based on the number 10, so converting units is done by adding or removing zeros (e.g. 1 centimetre = 10 millimetres, 1 decimetre = 10 centimetres, 1 meter = 100 centimetres, 1 dekametre = 10 meters, 1 kilometre = 1,000 meters).

Music

See also: Ten (disambiguation) § Art and entertainment

• The interval of a major tenth is an octave plus a major third.
• The interval of a minor tenth is an octave plus a minor third.

Religion

The tetractys

Abrahamic religions

The Ten Commandments in the Hebrew Bible are ethical commandments decreed by God (to Moses) for the people of Israel to follow.

Mysticism

• In Pythagoreanism, the number 10 played an important role and was symbolized by the tetractys.

• There are Ten Sephirot in the Kabbalistic Tree of Life.

• In Chinese astrology, the 10 Heavenly Stems, refer to a cyclic number system that is used also for time reckoning.

See also

• Mathematics portal
• List of highways numbered 10