Enter the number to be tested and the divisor into the calculator to determine the divisibility.

Divisibility Rules Formula

The following formula is used to calculate the divisibility of a number.

If N mod D = 0, then N is divisible by D

Variables:

  • N is the number to be tested for divisibility
  • D is the divisor mod is the modulus operator, which returns the remainder of a division operation

To calculate the divisibility of a number, divide the number to be tested (N) by the divisor (D). If the remainder of this division operation (N mod D) is 0, then the number is divisible by the divisor. If the remainder is not 0, then the number is not divisible by the divisor.

What is a Divisibility Rules?

Divisibility rules are simple guidelines used to determine whether one number can be evenly divided by another, without performing the actual division. These rules can help to quickly identify factors and simplify complex problems. For example, a number is divisible by 2 if its last digit is even, by 3 if the sum of its digits is divisible by 3, by 5 if its last digit is 0 or 5, and so on. Each number has its own unique rule or set of rules.

How to Calculate Divisibility Rules?

The following steps outline how to test for divisibility using the formula N mod D = 0:


  1. First, determine the number to be tested for divisibility (N).
  2. Next, determine the divisor (D).
  3. Next, use the modulus operator (mod) to calculate the remainder of the division operation N mod D.
  4. Finally, check if the remainder is equal to 0. If it is, then N is divisible by D. If not, then N is not divisible by D.

Example Problem:

Use the following variables as an example problem to test your knowledge:

Number to be tested for divisibility (N) = 27

Divisor (D) = 3

Using the formula N mod D = 0:

27 mod 3 = 0

Since the remainder is 0, 27 is divisible by 3.