Prime numbers are numbers that only have two factors, one and itself.

Examples of prime numbers are 2, 3, 5, 7, 11, 13, ….

Note: 1 is NOT a Prime number!!

## Perfect squares and perfect cubes

For a perfect square’s prime factorisation, each factor is to the **power of a multiple of 2.**

For a perfect cube’s prime factorisation, each factor is to the **power of a multiple of 3.**

## HCF & LCM

HCF, or Highest Common Factor, is the **greatest** common factor between two numbers.

LCM, or Lowest Common Multiple, is the **smallest common multiple **between two numbers.

## Laws of Indices

Check out: Indices and Logarithm Laws