What is 18?

In mathematics, 18 is a composite number, the second smallest number that is the sum of two distinct prime numbers (13 + 5), and the smallest number that is the sum of two unique prime numbers in the same way.

In Roman numerals, 18 is written as XVIII.

In science, 18 is the atomic number of argon, a noble gas.

In sports, the number 18 is commonly worn by football (soccer) players who play in the central midfield or attacking positions.

In some countries, the legal age of majority is 18, meaning individuals are considered adults and have certain rights and responsibilities.