Divisibility Rule for 23

If you divide a number by 23 and you get a whole number as an answer (quotient), then that number is divisible by 23.

Instead of simply dividing your number by 23 to see if you get a whole number, you can use what we call the Divisibility Rule for 23.

The Divisibility Rule for 23 is used to determine if a number is divisible by 23. You can also call it the test of divisibility for 23.

To determine if a number is divisible by 23, take the last digit and multiply it by 7. Then add that to the rest of the number. If the result is divisible by 23, then the number is divisible by 23.

For example, 575 is divisible by 23 because 57 + (5 x 7) = 92 and 92 is divisible by 23.

However, 576 is not divisible by 23 because 57 + (6 x 7) = 99, and 99 is not divisible by 23.

Divisibility Rule for 24
Here is the next Divisibility Rule on our list.

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