Change language18 in English words

eighteen

XVIII

even

Square root

4.2426406871193

Binary number

10010

18 in Fibonacci Sequence

No

This number consist from

2 digits

Sum of 2 digits (1+8)

9

Composite number (opposite to prime number).

Donations made by Jewish people often contain the number 18 (like $10.18), or are multiples of 18 (like $108.00). It's called “giving Chai”.