GCF (HCF) of 8 and 20

"Greatest Common Factor" Calculator
Greatest Common Factor of
and

What is the Greatest Common Divisor of 8 and 20?

Answer

GCF (HCF) of 8 and 20 is
4

Common factors: 1, 2, 4

4 divides both: 8 ÷ 4 = 2, 20 ÷ 4 = 5 — and 2 and 5 share no factor but 1, so no larger number divides both.

8 = 23

20 = 22 × 5

Prime820Lowest power
2232222
5—5—

— = power 0: the prime is not a factor of this number, so it cannot be in the GCF.

GCF = 22 = 4

More with these numbers

Related Calculations

See Also

GCF Table

Number 1Number 2GCF
831
844
851
862
891
8102
8111
8124
8131
8142
8151
8168
8171
8182
8191
8204
8211
8248
8251
8262
8271
8284
8291
8302
8328
8331
8351
8364
8408
8422

FAQ

What is the Greatest Common Divisor of 8 and 20?

GCF (HCF) of 8 and 20 is 4

How to find the GCF of 8 and 20?

You can find the GCF of 8 and 20 by listing all factors of both numbers and picking the greatest common one, or by prime factorization. The GCF of 8 and 20 is 4.

What prime factors do 8 and 20 share?

The prime factorizations of 8 and 20 have 2 × 2 in common, and multiplying those shared primes gives 4 — exactly the greatest common factor.

How does the GCF reduce the fraction 8/20?

Divide the numerator and the denominator by the GCF 4: 8 ÷ 4 = 2 and 20 ÷ 4 = 5. So 8/20 in lowest terms is 2/5.

See Also