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 17, 21 i.e. 1 largest integer by which both the numbers can be divided.
Greatest common factor (GCF) of 17 and 21 is 1.
GCF(17,21) = 1
Greatest common factor or Greatest common divisor (GCD) can be calculated in following way;
Prime Factorization of 17
17 | 17 |
1 |
Prime factors of 17 are 17. Prime factorization of 17 in exponential form is:
17 = 171
Prime Factorization of 21
3 | 21 |
7 | 7 |
1 |
Prime factors of 21 are 3.Prime factorization of 21 in exponential form is:
21 = 31×71
∴ So by taking common prime factors GCF of 17 and 21 is 1
Factors of 17
List of positive integer factors of 17 that divides 17 without a remainder.
1,17
Factors of 21
List of positive integer factors of 21 that divides 21 without a remainder.
1,3,7,21
Greatest Common Factor
We found the factors and prime factorization of 17 and 21. The biggest common factor number is the GCF number.
So the greatest common factor 17 and 21 is 1.
Also check out the Least Common Multiple of 17 and 21
(i) The GCF of 17 and 21 is associative
GCF of 17 and 21 = GCF of 21 and 17
1. What is the GCF of 17 and 21?
Answer: GCF of 17 and 21 is 1.
2. What are the Factors of 17?
Answer: Factors of 17 are 1, 17. There are 2 integers that are factors of 17. The greatest factor of 17 is 17.
3. What are the Factors of 21?
Answer: Factors of 21 are 1, 3, 7, 21. There are 4 integers that are factors of 21. The greatest factor of 21 is 21.
4. How to Find the GCF of 17 and 21?
Answer:
Greatest Common Factor of 17 and 21 = 1
Step 1: Find the prime factorization of 17
17 = 17
Step 2: Find the prime factorization of 21
21 = 3 x 7
Step 3: Multiply those factors both numbers have in common in steps i) or ii) above to find the gcf:
GCF = = 1
Step 4: Therefore, the greatest common factor of 17 and 21 is 1