Divisibility Rule for 18

If you divide a number by 18 and you get a whole number as an answer (quotient), then that number is divisible by 18.

Instead of simply dividing your number by 18 to see if you get a whole number, you can use what we call the Divisibility Rule for 18.

The Divisibility Rule for 18 is used to determine if a number is divisible by 18. You can also call it the test of divisibility for 18.

A number is divisible by 18 if it is an even number AND the sum of its digits is divisible by 9.

For example, 492,480 is divisible by 18 because it is an even number and the sum of its digits is 4 + 9 + 2 + 4 + 8 + 0 = 27 is divisible by 9.

However, 246,802 is not divisible by 18 because although it is an even number, the sum of its digits is 2 + 4 + 6 + 8 + 0 + 2 = 22 is not divisible by 9.

Remember, both conditions must be met for the number to be divisible by 18.

Divisibility Rule for 19
Here is the next Divisibility Rule on our list.

Divisibility Rules
Here is a list of all our Divisibility Rules.