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 1985, 1991 i.e. 1 largest integer by which both the numbers can be divided.
Greatest common factor (GCF) of 1985 and 1991 is 1.
GCF(1985,1991) = 1
Greatest common factor or Greatest common divisor (GCD) can be calculated in following way;
Prime Factorization of 1985
5 | 1985 |
397 | 397 |
1 |
Prime factors of 1985 are 5,397. Prime factorization of 1985 in exponential form is:
1985 = 51×3971
Prime Factorization of 1991
11 | 1991 |
181 | 181 |
1 |
Prime factors of 1991 are 11,181. Prime factorization of 1991 in exponential form is:
1991 = 111×1811
∴ So by taking common prime factors GCF of 1985 and 1991 is 1
Factors of 1985
List of positive integer factors of 1985 that divides 1985 without a remainder.
1,5,397,1985
Factors of 1991
List of positive integer factors of 1991 that divides 1991 without a remainder.
1,11,181,1991
Greatest Common Factor
We found the factors and prime factorization of 1985 and 1991. The biggest common factor number is the GCF number.
So the greatest common factor 1985 and 1991 is 1.
Also check out the Least Common Multiple of 1985 and 1991
(i) The GCF of 1985 and 1991 is associative
GCF of 1985 and 1991 = GCF of 1991 and 1985
1. What is the GCF of 1985 and 1991?
Answer: GCF of 1985 and 1991 is 1.
2. What are the Factors of 1985?
Answer: Factors of 1985 are 1, 5, 397, 1985. There are 4 integers that are factors of 1985. The greatest factor of 1985 is 1985.
3. What are the Factors of 1991?
Answer: Factors of 1991 are 1, 11, 181, 1991. There are 4 integers that are factors of 1991. The greatest factor of 1991 is 1991.
4. How to Find the GCF of 1985 and 1991?
Answer:
Greatest Common Factor of 1985 and 1991 = 1
Step 1: Find the prime factorization of 1985
1985 = 5 x 397
Step 2: Find the prime factorization of 1991
1991 = 11 x 181
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 1985 and 1991 is 1