What is the Greatest Common Factor of 20405 and 20409?

Greatest common factor (GCF) of 20405 and 20409 is 1.

GCF(20405,20409) = 1

We will now calculate the prime factors of 20405 and 20409, than find the greatest common factor (greatest common divisor (gcd)) of the numbers by matching the biggest common factor of 20405 and 20409.

How to find the GCF of 20405 and 20409?

We will first find the prime factorization of 20405 and 20409. After we will calculate the factors of 20405 and 20409 and find the biggest common factor number .

Step-1: Prime Factorization of 20405

Prime factors of 20405 are 5, 7, 11, 53. Prime factorization of 20405 in exponential form is:

20405 = 5¹ × 7¹ × 11¹ × 53¹

Step-2: Prime Factorization of 20409

Prime factors of 20409 are 3, 6803. Prime factorization of 20409 in exponential form is:

20409 = 3¹ × 6803¹

Step-3: Factors of 20405

List of positive integer factors of 20405 that divides 20405 without a remainder.

1, 5, 7, 11, 35, 53, 55, 77, 265, 371, 385, 583, 1855, 2915, 4081

Step-4: Factors of 20409

List of positive integer factors of 20409 that divides 20405 without a remainder.

1, 3, 6803

Final Step: Biggest Common Factor Number

We found the factors and prime factorization of 20405 and 20409. The biggest common factor number is the GCF number.
So the greatest common factor 20405 and 20409 is 1.

Also check out the Least Common Multiple of 20405 and 20409