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18 (number)

natural number
(Redirected from Eighteen)

Eighteen is a number. It comes between seventeen and nineteen, and is an even number. It is divisible by 1, 2, 3, 6, 9 and 18. In most countries it is the age of majority, age of consent, and voting age.

← 17 18 19 →
Cardinaleighteen
Ordinal18th
(eighteenth)
Factorization2 × 32
Greek numeralΙΗ´
Roman numeralXVIII
Binary100102
Ternary2003
Quaternary1024
Quinary335
Senary306
Octal228
Duodecimal1612
Hexadecimal1216
VigesimalI20
Base 36I36

In Roman numerals, 18 is written as XVIII.

The number 18 has many multiples such as: 36, 54, 72, 90, 108, and so on. The prime factorization of 18 is 3x3x2 in expanded form, and 3^2x2 in factored form.