What is the Greatest Common Factor of 21745 and 21765?

Greatest common factor (GCF) of 21745 and 21765 is 5.

GCF(21745,21765) = 5

We will now calculate the prime factors of 21745 and 21765, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21745 and 21765.

How to find the GCF of 21745 and 21765?

We will first find the prime factorization of 21745 and 21765. After we will calculate the factors of 21745 and 21765 and find the biggest common factor number .

Step-1: Prime Factorization of 21745

Prime factors of 21745 are 5, 4349. Prime factorization of 21745 in exponential form is:

21745 = 5¹ × 4349¹

Step-2: Prime Factorization of 21765

Prime factors of 21765 are 3, 5, 1451. Prime factorization of 21765 in exponential form is:

21765 = 3¹ × 5¹ × 1451¹

Step-3: Factors of 21745

List of positive integer factors of 21745 that divides 21745 without a remainder.

1, 5, 4349

Step-4: Factors of 21765

List of positive integer factors of 21765 that divides 21745 without a remainder.

1, 3, 5, 15, 1451, 4353, 7255

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21745 and 21765. The biggest common factor number is the GCF number.
So the greatest common factor 21745 and 21765 is 5.

Also check out the Least Common Multiple of 21745 and 21765