GCF (HCF) of 21 and 37

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What is the Greatest Common Divisor of 21 and 37?

Answer

GCF (HCF) of 21 and 37 is
1

Common factors: 1

Only 1 divides both: 21 and 37 share no prime factor.

Such numbers are called coprime (relatively prime); their LCM is just the product: 21 × 37 = 777.

21 = 3 × 7

37 — prime

Prime2137Lowest power
33——
77——
37—37—

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

GCF = 1

See Also

FAQ

What is the Greatest Common Divisor of 21 and 37?

GCF (HCF) of 21 and 37 is 1

How to find the GCF of 21 and 37?

You can find the GCF of 21 and 37 by listing all factors of both numbers and picking the greatest common one, or by prime factorization. The GCF of 21 and 37 is 1.

What prime factors do 21 and 37 share?

21 and 37 have no prime factor in common, so the only integer that divides both of them is 1 and their GCF is 1.

How does the GCF reduce the fraction 21/37?

Divide the numerator and the denominator by the GCF 1: 21 ÷ 1 = 21 and 37 ÷ 1 = 37. So 21/37 in lowest terms is 21/37.

Are 21 and 37 coprime?

Yes, 21 and 37 are coprime (relatively prime) because their Greatest Common Factor is 1.