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What is the Greatest Common Factor of 20991 and 21007?

Greatest common factor (GCF) of 20991 and 21007 is 1.

GCF(20991,21007) = 1

We will now calculate the prime factors of 20991 and 21007, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 20991 and 21007.

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How to find the GCF of 20991 and 21007?

We will first find the prime factorization of 20991 and 21007. After we will calculate the factors of 20991 and 21007 and find the biggest common factor number .

Step-1: Prime Factorization of 20991

Prime factors of 20991 are 3, 6997. Prime factorization of 20991 in exponential form is:

20991 = 31 × 69971

Step-2: Prime Factorization of 21007

Prime factors of 21007 are 7, 3001. Prime factorization of 21007 in exponential form is:

21007 = 71 × 30011

Step-3: Factors of 20991

List of positive integer factors of 20991 that divides 20991 without a remainder.

1, 3, 6997

Step-4: Factors of 21007

List of positive integer factors of 21007 that divides 20991 without a remainder.

1, 7, 3001

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 20991 and 21007. The biggest common factor number is the GCF number.
So the greatest common factor 20991 and 21007 is 1.

Also check out the Least Common Multiple of 20991 and 21007