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 640, 644 i.e. 4 largest integer by which both the numbers can be divided.
Greatest common factor (GCF) of 640 and 644 is 4.
GCF(640,644) = 4
Greatest common factor or Greatest common divisor (GCD) can be calculated in following way;
Prime Factorization of 640
2 | 640 |
2 | 320 |
2 | 160 |
2 | 80 |
2 | 40 |
2 | 20 |
2 | 10 |
5 | 5 |
1 |
Prime factors of 640 are 2,5. Prime factorization of 640 in exponential form is:
640 = 27×51
Prime Factorization of 644
2 | 644 |
2 | 322 |
7 | 161 |
23 | 23 |
1 |
Prime factors of 644 are 2,7,23. Prime factorization of 644 in exponential form is:
644 = 22×71×231
∴ So by taking common prime factors GCF of 640 and 644 is 4
Factors of 640
List of positive integer factors of 640 that divides 640 without a remainder.
1,2,4,5,8,10,16,20,32,40,64,80,128,160,320,640
Factors of 644
List of positive integer factors of 644 that divides 644 without a remainder.
1,2,4,7,14,23,28,46,92,161,322,644
Greatest Common Factor
We found the factors and prime factorization of 640 and 644. The biggest common factor number is the GCF number.
So the greatest common factor 640 and 644 is 4.
Also check out the Least Common Multiple of 640 and 644
(i) The GCF of 640 and 644 is associative
GCF of 640 and 644 = GCF of 644 and 640
1. What is the GCF of 640 and 644?
Answer: GCF of 640 and 644 is 4.
2. What are the Factors of 640?
Answer: Factors of 640 are 1, 2, 4, 5, 8, 10, 16, 20, 32, 40, 64, 80, 128, 160, 320, 640. There are 16 integers that are factors of 640. The greatest factor of 640 is 640.
3. What are the Factors of 644?
Answer: Factors of 644 are 1, 2, 4, 7, 14, 23, 28, 46, 92, 161, 322, 644. There are 12 integers that are factors of 644. The greatest factor of 644 is 644.
4. How to Find the GCF of 640 and 644?
Answer:
Greatest Common Factor of 640 and 644 = 4
Step 1: Find the prime factorization of 640
640 = 2 x 2 x 2 x 2 x 2 x 2 x 2 x 5
Step 2: Find the prime factorization of 644
644 = 2 x 2 x 7 x 23
Step 3: Multiply those factors both numbers have in common in steps i) or ii) above to find the gcf:
GCF = 2 x 2 = 4
Step 4: Therefore, the greatest common factor of 640 and 644 is 4