What is the Greatest Common Factor of 21705 and 21709?

Greatest common factor (GCF) of 21705 and 21709 is 1.

GCF(21705,21709) = 1

We will now calculate the prime factors of 21705 and 21709, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21705 and 21709.

How to find the GCF of 21705 and 21709?

We will first find the prime factorization of 21705 and 21709. After we will calculate the factors of 21705 and 21709 and find the biggest common factor number .

Step-1: Prime Factorization of 21705

Prime factors of 21705 are 3, 5, 1447. Prime factorization of 21705 in exponential form is:

21705 = 3¹ × 5¹ × 1447¹

Step-2: Prime Factorization of 21709

Prime factors of 21709 are 17, 1277. Prime factorization of 21709 in exponential form is:

21709 = 17¹ × 1277¹

Step-3: Factors of 21705

List of positive integer factors of 21705 that divides 21705 without a remainder.

1, 3, 5, 15, 1447, 4341, 7235

Step-4: Factors of 21709

List of positive integer factors of 21709 that divides 21705 without a remainder.

1, 17, 1277

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21705 and 21709. The biggest common factor number is the GCF number.
So the greatest common factor 21705 and 21709 is 1.

Also check out the Least Common Multiple of 21705 and 21709