What is the Greatest Common Factor of 21670 and 21686?

Greatest common factor (GCF) of 21670 and 21686 is 2.

GCF(21670,21686) = 2

We will now calculate the prime factors of 21670 and 21686, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21670 and 21686.

How to find the GCF of 21670 and 21686?

We will first find the prime factorization of 21670 and 21686. After we will calculate the factors of 21670 and 21686 and find the biggest common factor number .

Step-1: 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-2: Prime Factorization of 21686

Prime factors of 21686 are 2, 7, 1549. Prime factorization of 21686 in exponential form is:

21686 = 2¹ × 7¹ × 1549¹

Step-3: Factors of 21670

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

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

Step-4: Factors of 21686

List of positive integer factors of 21686 that divides 21670 without a remainder.

1, 2, 7, 14, 1549, 3098, 10843

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21670 and 21686. The biggest common factor number is the GCF number.
So the greatest common factor 21670 and 21686 is 2.

Also check out the Least Common Multiple of 21670 and 21686