What is the Greatest Common Factor of 21681 and 21687?

Greatest common factor (GCF) of 21681 and 21687 is 3.

GCF(21681,21687) = 3

We will now calculate the prime factors of 21681 and 21687, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21681 and 21687.

How to find the GCF of 21681 and 21687?

We will first find the prime factorization of 21681 and 21687. After we will calculate the factors of 21681 and 21687 and find the biggest common factor number .

Step-1: Prime Factorization of 21681

Prime factors of 21681 are 3, 11, 73. Prime factorization of 21681 in exponential form is:

21681 = 3³ × 11¹ × 73¹

Step-2: Prime Factorization of 21687

Prime factors of 21687 are 3, 7229. Prime factorization of 21687 in exponential form is:

21687 = 3¹ × 7229¹

Step-3: Factors of 21681

List of positive integer factors of 21681 that divides 21681 without a remainder.

1, 3, 9, 11, 27, 33, 73, 99, 219, 297, 657, 803, 1971, 2409, 7227

Step-4: Factors of 21687

List of positive integer factors of 21687 that divides 21681 without a remainder.

1, 3, 7229

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21681 and 21687. The biggest common factor number is the GCF number.
So the greatest common factor 21681 and 21687 is 3.

Also check out the Least Common Multiple of 21681 and 21687