What is the Greatest Common Factor of 21655 and 21670?

Greatest common factor (GCF) of 21655 and 21670 is 5.

GCF(21655,21670) = 5

We will now calculate the prime factors of 21655 and 21670, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21655 and 21670.

How to find the GCF of 21655 and 21670?

We will first find the prime factorization of 21655 and 21670. After we will calculate the factors of 21655 and 21670 and find the biggest common factor number .

Step-1: Prime Factorization of 21655

Prime factors of 21655 are 5, 61, 71. Prime factorization of 21655 in exponential form is:

21655 = 5¹ × 61¹ × 71¹

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 21655

List of positive integer factors of 21655 that divides 21655 without a remainder.

1, 5, 61, 71, 305, 355, 4331

Step-4: Factors of 21670

List of positive integer factors of 21670 that divides 21655 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 21655 and 21670. The biggest common factor number is the GCF number.
So the greatest common factor 21655 and 21670 is 5.

Also check out the Least Common Multiple of 21655 and 21670