18 (also written as eighteen or ten-eight) 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.
|Factorization||2 × 32|
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 2x3² in factored form.