Factors
Numbers which divide exactly into a higher number
are said to be factors of the higher number.
For example 2 x 3 = 6.
 2 and 3 are factors of 6

Highest common factor

If you work out the factors of two
different  numbers the highest common
factor (HCF) is the highest number  that appears
In both lists

Prime Factors

The prime factors of a number are the
prime numbers which when multiplied
together  produce the number
For example the prime factors of 12 are
2, 2, and 3 (check 2 x 2 x 3 =12)
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