Prime Factors

What are Prime Factors ?

Prime factors are factors of a number that are, themselves, prime numbers.

2 and 3 are prime factors of 12.

What is a Prime Factor Tree ?

A prime factor tree is a visual aid used to find the prime factors of a number. The prime factors of 60 are 2, 3 and 5.

  60
 /  \
2   30
    / \
   2   15
       / \
      3   5

  60
 /  \
3   20
    / \
   2  10
      / \
     2   5

    60
   /  \
  4    15
 / \   / \
2   2 3   5

  60
 /  \
5    12
     / \
    2   6
       / \
      2   3

    60
   /  \
  6    10
 / \   / \
2   3 2   5

Expressing a Number as a Product of it’s Prime Factors

A number can be written down or expressed as product of it’s prime factors by multiplying them together.

In the above examples, the number 2 appears twice so it’s used twice as follows.

2 x 2 x 3 x 5 = 2^2 x 3 x 5 = 60

Factors vs Prime Factors

A factor is a number that divides into another number exactly and without leaving a remainder. Whereas Prime factors are factors of a number that are, themselves, prime numbers.

See Also

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