Divisibility Rules

This video will give you a quick review of divisibility rules:
A number is divisible by 2: when the number is even
by 3: when the sum of the digits is divisible by 3
by 4: when the last two digits are divisible by 4
by 5: the last digit is zero or 5
by 6: the number is divisible by 2 and 3
by 9: the sum of its digits is divisible by 9

Here you can see the number 420 as an example.