What is the Greatest Common Factor of 21972 and 21985?

Greatest common factor (GCF) of 21972 and 21985 is 1.

GCF(21972,21985) = 1

We will now calculate the prime factors of 21972 and 21985, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21972 and 21985.

How to find the GCF of 21972 and 21985?

We will first find the prime factorization of 21972 and 21985. After we will calculate the factors of 21972 and 21985 and find the biggest common factor number .

Step-1: Prime Factorization of 21972

Prime factors of 21972 are 2, 3, 1831. Prime factorization of 21972 in exponential form is:

21972 = 2² × 3¹ × 1831¹

Step-2: Prime Factorization of 21985

Prime factors of 21985 are 5, 4397. Prime factorization of 21985 in exponential form is:

21985 = 5¹ × 4397¹

Step-3: Factors of 21972

List of positive integer factors of 21972 that divides 21972 without a remainder.

1, 2, 3, 4, 6, 12, 1831, 3662, 5493, 7324, 10986

Step-4: Factors of 21985

List of positive integer factors of 21985 that divides 21972 without a remainder.

1, 5, 4397

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21972 and 21985. The biggest common factor number is the GCF number.
So the greatest common factor 21972 and 21985 is 1.

Also check out the Least Common Multiple of 21972 and 21985