What is the Greatest Common Factor of 21665 and 21670?

Greatest common factor (GCF) of 21665 and 21670 is 5.

GCF(21665,21670) = 5

We will now calculate the prime factors of 21665 and 21670, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21665 and 21670.

How to find the GCF of 21665 and 21670?

We will first find the prime factorization of 21665 and 21670. After we will calculate the factors of 21665 and 21670 and find the biggest common factor number .

Step-1: Prime Factorization of 21665

Prime factors of 21665 are 5, 7, 619. Prime factorization of 21665 in exponential form is:

21665 = 5¹ × 7¹ × 619¹

Step-2: Prime Factorization of 21670

Prime factors of 21670 are 2, 5, 11, 197. Prime factorization of 21670 in exponential form is:

21670 = 2¹ × 5¹ × 11¹ × 197¹

Step-3: Factors of 21665

List of positive integer factors of 21665 that divides 21665 without a remainder.

1, 5, 7, 35, 619, 3095, 4333

Step-4: Factors of 21670

List of positive integer factors of 21670 that divides 21665 without a remainder.

1, 2, 5, 10, 11, 22, 55, 110, 197, 394, 985, 1970, 2167, 4334, 10835

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21665 and 21670. The biggest common factor number is the GCF number.
So the greatest common factor 21665 and 21670 is 5.

Also check out the Least Common Multiple of 21665 and 21670