What is the Greatest Common Factor of 71991 and 72009?

Greatest common factor (GCF) of 71991 and 72009 is 9.

GCF(71991,72009) = 9

We will now calculate the prime factors of 71991 and 72009, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 71991 and 72009.

How to find the GCF of 71991 and 72009?

We will first find the prime factorization of 71991 and 72009. After we will calculate the factors of 71991 and 72009 and find the biggest common factor number .

Step-1: Prime Factorization of 71991

Prime factors of 71991 are 3, 19, 421. Prime factorization of 71991 in exponential form is:

71991 = 3² × 19¹ × 421¹

Step-2: Prime Factorization of 72009

Prime factors of 72009 are 3, 7, 127. Prime factorization of 72009 in exponential form is:

72009 = 3⁴ × 7¹ × 127¹

Step-3: Factors of 71991

List of positive integer factors of 71991 that divides 71991 without a remainder.

1, 3, 9, 19, 57, 171, 421, 1263, 3789, 7999, 23997

Step-4: Factors of 72009

List of positive integer factors of 72009 that divides 71991 without a remainder.

1, 3, 7, 9, 21, 27, 63, 81, 127, 189, 381, 567, 889, 1143, 2667, 3429, 8001, 10287, 24003

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 71991 and 72009. The biggest common factor number is the GCF number.
So the greatest common factor 71991 and 72009 is 9.

Also check out the Least Common Multiple of 71991 and 72009