What is the Greatest Common Factor of 19991 and 20009?

Greatest common factor (GCF) of 19991 and 20009 is 1.

GCF(19991,20009) = 1

We will now calculate the prime factors of 19991 and 20009, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 19991 and 20009.

How to find the GCF of 19991 and 20009?

We will first find the prime factorization of 19991 and 20009. After we will calculate the factors of 19991 and 20009 and find the biggest common factor number .

Step-1: Prime Factorization of 19991

Prime factors of 19991 are 19991. Prime factorization of 19991 in exponential form is:

19991 = 19991¹

Step-2: Prime Factorization of 20009

Prime factors of 20009 are 11, 17, 107. Prime factorization of 20009 in exponential form is:

20009 = 11¹ × 17¹ × 107¹

Step-3: Factors of 19991

List of positive integer factors of 19991 that divides 19991 without a remainder.

Step-4: Factors of 20009

List of positive integer factors of 20009 that divides 19991 without a remainder.

1, 11, 17, 107, 187, 1177, 1819

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 19991 and 20009. The biggest common factor number is the GCF number.
So the greatest common factor 19991 and 20009 is 1.

Also check out the Least Common Multiple of 19991 and 20009