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What is the Greatest Common Factor of 21509 and 21521?

Greatest common factor (GCF) of 21509 and 21521 is 1.

GCF(21509,21521) = 1

We will now calculate the prime factors of 21509 and 21521, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 21509 and 21521.

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How to find the GCF of 21509 and 21521?

We will first find the prime factorization of 21509 and 21521. After we will calculate the factors of 21509 and 21521 and find the biggest common factor number .

Step-1: Prime Factorization of 21509

Prime factors of 21509 are 137, 157. Prime factorization of 21509 in exponential form is:

21509 = 1371 × 1571

Step-2: Prime Factorization of 21521

Prime factors of 21521 are 21521. Prime factorization of 21521 in exponential form is:

21521 = 215211

Step-3: Factors of 21509

List of positive integer factors of 21509 that divides 21509 without a remainder.

1, 137, 157

Step-4: Factors of 21521

List of positive integer factors of 21521 that divides 21509 without a remainder.

1

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 21509 and 21521. The biggest common factor number is the GCF number.
So the greatest common factor 21509 and 21521 is 1.

Also check out the Least Common Multiple of 21509 and 21521