What are the divisibility rules?

1- Any number is divisible by 1.

2- Any even number is divisible by 2.

3- If its digits add up to a number divisible by 3, the whole number is divisible by 3.

4- If the last two digits are divisible by 4, the whole number is divisible by 4.

5- If it ends in 5 or 0, the whole number is divisible by 5.

6- If it's even and also divisible by 3, the whole number is divisible by 6.

7- There is no rule for 7.

8- If the last three digits are divisible by 8, the whole number is divisible by 8.

9- If its digits add up to a number divisible by 9, the whole number is divisible by 9.

10- If it ends in 0, the whole number is divisible by 10.

divisibilty rules are how you times the number for instence if you want to find the divisibilty rule for 10 it would be the end number must be zero and then it would be a multiple of 10 and the divisibilty rule for 2 is the end number must be even then it would be a multiple of 2

There are guidelines that exist to tell whether a number is divisible by another without having to perform the division. For example, if a number ends in 0 or 5, it is divisible by 5. That's the divisibility rule for 5.
You can find out if a number is divisible by another by trial and error, that is, actually dividing it. If you know the divisibility rules, you can tell whether one number is divisible by another just by looking at it. For example, if a number is even, it's divisible by 2. If the sum of a number's digits adds up to a multiple of 3, the original number is divisible by 3. If a number ends in 0 or 5, it's divisible by 5.