What is the prime factorization of 8?

8 = 2 × 2 × 2 = 2³. The only prime factor of 8 is 2.

How many factor pairs does 8 have?

Two: (1, 8) and (2, 4). Since 8 is not a perfect square, every factor has a different partner.

What is the greatest common factor of 8 and 12?

The GCF of 8 and 12 is 4. The common factors are 1, 2 and 4, and 4 is the largest.

Factors of 8 - Pairs, Prime Factorization & Examples

Q: What are the factors of 8?

The factors of 8 are 1, 2, 4 and 8. That is four factors.

What Are the Factors of 8?

Cut a pizza into 8 slices and you can share it with 1, 2, 4 or 8 people without a single slice left over. Each of those group sizes is a factor. A factor is a whole number that divides another number exactly, with no remainder.

The factors of 8 are 1, 2, 4 and 8. That is four factors, and every one of them is a power of 2.

Factor Pairs of 8

Do not test numbers at random. Look for pairs that multiply to 8, working from the outside in.

Handwritten notebook page titled Factors of 8 showing 1 × 8 = 8 and 2 × 4 = 8, with the four factors 1, 2, 4 and 8 circled in red and the note 4 factors — The two pairs of 8, then each factor circled.

Start with 1 × 8. Every number has this pair.
Try 2. Since 8 ÷ 2 = 4, write 2 × 4.
Try 3. It leaves a remainder, and the next number to test would be 4, which is already written, so you are done.

Prime Factorization of 8 With a Factor Tree

Prime factors show what 8 is built from. Split it into two numbers, then keep splitting until every branch is a prime.

Handwritten factor tree of 8 splitting into 2 and 4, then 4 into 2 and 2, with all three 2s circled in red and 8 = 2 × 2 × 2 = 2³ written below — Factor tree of 8. Three circled 2s mean 2 × 2 × 2.

So 8 = 2 × 2 × 2 = 2³. Only one prime appears, the number 2, used three times.

Count the factors with the exponent

Add 1 to the exponent: 3 + 1 = 4. That matches the four factors we listed, and the trick works for any power of a single prime.

Is 8 a Prime or Composite Number?

Composite. It has four factors instead of two. It is also a cube number, since 2 × 2 × 2 = 8. The factors add up to 1 + 2 + 4 + 8 = 15.

Real-Life Uses of the Factors of 8

Computers. A byte is 8 bits, so memory sizes keep doubling in neat steps of 2.
Music. An octave spans 8 notes, which split into groups of 2 or 4 beats.
A work day. Eight hours divides into two 4-hour halves or four 2-hour blocks.

Common Factors of 8 With Other Numbers

The factors of 12 are 1, 2, 3, 4, 6 and 12, so 8 and 12 share 1, 2 and 4. The GCF is 4, and it simplifies 8/12 to 2/3.

Quick Practice

Which of these are factors of 8: 3, 4 or 6? Only 4. 8 ÷ 3 leaves 2 and 8 ÷ 6 leaves 2. Now try 16 and compare it with the calculator.

Factors of 8