GCF for 5, 12 and 20

"Greatest Common Factor of 3 Numbers" Calculator
Greatest Common Factor of
,
and

What's the Greatest Common Factor (GCF) of 5, 12 and 20?

Answer

GCF of 5, 12 and 20 is
1

Common factors: 1

Only 1 divides all three: no prime is a factor of each of 5, 12 and 20.

Pairs do share factors — GCF(5, 20) = 5, GCF(12, 20) = 4 — just none greater than 1 common to all three.

5 — prime

12 = 22 × 3

20 = 22 × 5

Prime51220Lowest power
2—2222—
3—3——
55—5—

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

GCF = 1

More with these numbers

Related Calculations

See Also

GCF Table

1st2nd3rdGCF
55121
56121
57121
58121
59121
510121
511121
512121
512131
512141
512151
512161
512171
512181
512191
512201
512211
512221
512231
512241
512251
512261
512271
512281
512291
512301
512311
512321
512331
512341

FAQ

What's the Greatest Common Factor (GCF) of 5, 12 and 20?

GCF of 5, 12 and 20 is 1

What prime factors do 5, 12 and 20 share?

None at all: 5, 12 and 20 have no prime factor in common, so the only positive integer dividing all three is 1 and their GCF is 1.

Can you get the GCF of 5, 12 and 20 two numbers at a time?

Yes. The GCF of 5 and 12 is 1, and the GCF of 1 and 20 is 1 — the same answer, because the greatest common factor is associative and does not depend on the order of the three numbers.

How does the GCF simplify the ratio 5 : 12 : 20?

Divide every term by the GCF 1: 5 ÷ 1 = 5, 12 ÷ 1 = 12 and 20 ÷ 1 = 20. So 5 : 12 : 20 in lowest terms is 5 : 12 : 20, and no whole number other than 1 divides all three of those.

See Also