What is the Greatest Common Factor of 21809 and 21821?

Greatest common factor (GCF) of 21809 and 21821 is 1.

GCF(21809,21821) = 1

We will now calculate the prime factors of 21809 and 21821, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21809 and 21821.

How to find the GCF of 21809 and 21821?

We will first find the prime factorization of 21809 and 21821. After we will calculate the factors of 21809 and 21821 and find the biggest common factor number .

Step-1: Prime Factorization of 21809

Prime factors of 21809 are 113, 193. Prime factorization of 21809 in exponential form is:

21809 = 113¹ × 193¹

Step-2: Prime Factorization of 21821

Prime factors of 21821 are 21821. Prime factorization of 21821 in exponential form is:

21821 = 21821¹

Step-3: Factors of 21809

List of positive integer factors of 21809 that divides 21809 without a remainder.

1, 113, 193

Step-4: Factors of 21821

List of positive integer factors of 21821 that divides 21809 without a remainder.

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21809 and 21821. The biggest common factor number is the GCF number.
So the greatest common factor 21809 and 21821 is 1.

Also check out the Least Common Multiple of 21809 and 21821