Greatest Common Factor of 399 and 405

Created By : Jatin Gogia

Reviewed By : Rajasekhar Valipishetty

Last Updated : Apr 06, 2023


Make use of GCF Calculator to quickly find the Greatest Common Factor of numbers 399, 405 i.e. 3 largest integer by which both the numbers can be divided.

Greatest common factor (GCF) of 399 and 405 is 3.

GCF(399,405) = 3

GCF of 399 and 405

Greatest common factor or Greatest common divisor (GCD) can be calculated in following way;

GCF of:
and

Greatest Common Factor of 399 and 405

GCF of 399 and 405 is 3

Prime Factorization of 399


3 399
7 133
19 19
1

Prime factors of 399 are 3,7,19. Prime factorization of 399 in exponential form is:

399 = 31×71×191

Prime Factorization of 405


3 405
3 135
3 45
3 15
5 5
1

Prime factors of 405 are 3,5. Prime factorization of 405 in exponential form is:

405 = 34×51

∴ So by taking common prime factors GCF of 399 and 405 is 3

Greatest Common Factor of 399 and 405 by matching factors method

Factors of 399

List of positive integer factors of 399 that divides 399 without a remainder.

1,3,7,19,21,57,133,399

Factors of 405

List of positive integer factors of 405 that divides 405 without a remainder.

1,3,5,9,15,27,45,81,135,405

Greatest Common Factor

We found the factors and prime factorization of 399 and 405. The biggest common factor number is the GCF number.
So the greatest common factor 399 and 405 is 3.

Also check out the Least Common Multiple of 399 and 405

Properties of GCF 399 and 405

(i) The GCF of 399 and 405 is associative

GCF of 399 and 405 = GCF of 405 and 399

Frequently Asked Questions on GCF of 399 and 405

1. What is the GCF of 399 and 405?

Answer: GCF of 399 and 405 is 3.

2. What are the Factors of 399?

Answer: Factors of 399 are 1, 3, 7, 19, 21, 57, 133, 399. There are 8 integers that are factors of 399. The greatest factor of 399 is 399.

3. What are the Factors of 405?

Answer: Factors of 405 are 1, 3, 5, 9, 15, 27, 45, 81, 135, 405. There are 10 integers that are factors of 405. The greatest factor of 405 is 405.

4. How to Find the GCF of 399 and 405?

Answer:

Greatest Common Factor of 399 and 405 = 3

Step 1: Find the prime factorization of 399

399 = 3 x 7 x 19

Step 2: Find the prime factorization of 405

405 = 3 x 3 x 3 x 3 x 5

Step 3: Multiply those factors both numbers have in common in steps i) or ii) above to find the gcf:

GCF = 3

Step 4: Therefore, the greatest common factor of 399 and 405 is 3