Least Common Multiple of 1987 and 1991

Created By : Jatin Gogia

Reviewed By : Rajasekhar Valipishetty

Last Updated : Apr 06, 2023

Free LCM Calculator determines the least common multiple (LCM) between 1987 and 1991 the smallest integer that is 3956117 that is divisible by both numbers.

Least Common Multiple (LCM) of 1987 and 1991 is 3956117.

LCM(1987,1991) = 3956117

LCM of 1987 and 1991

Least common multiple or lowest common denominator (LCD) can be calculated in three ways;

LCM of:
and

Least Common Multiple of 1987 and 1991

LCM of 1987 and 1991 is 3956117

Least common multiple can be found by multiplying the highest exponent prime factors of 1987 and 1991. First we will calculate the prime factors of 1987 and 1991.

Prime Factorization of 1987


1987 1987
1

Prime factors of 1987 are 1987. Prime factorization of 1987 in exponential form is:

1987 = 19871

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

Now multiplying the highest exponent prime factors to calculate the LCM of 1987 and 1991.

LCM(1987,1991) = 111×1811×19871
LCM(1987,1991) = 3956117

Factors of 1987

List of positive integer factors of 1987 that divides 1987 without a remainder.

1, 1987

Factors of 1991

List of positive integer factors of 1991 that divides 1991 without a remainder.

1, 11, 181, 1991

Least Common Multiple of 1987 and 1991 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 1987 and 1991, than apply into the LCM equation.

GCF(1987,1991) = 1
LCM(1987,1991) = ( 1987 × 1991) / 1
LCM(1987,1991) = 3956117 / 1
LCM(1987,1991) = 3956117

Properties of LCM 1987 and 1991

(i) The LCM of 1991 and 1987 is associative

LCM of 1987 and 1991 = LCM of 1991 and 1987

Related Least Common Multiples of 1987

Related Least Common Multiples of 1991

Frequently Asked Questions on LCM of 1987 and 1991

1. What is the LCM of 1987 and 1991?

Answer: LCM of 1987 and 1991 is 3956117.

2. What are the Factors of 1987?

Answer: Factors of 1987 are 1, 1987. There are 2 integers that are factors of 1987. The greatest factor of 1987 is 1987.

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 LCM of 1987 and 1991?

Answer:

Least Common Multiple of 1987 and 1991 = 3956117

Step 1: Find the prime factorization of 1987

1987 = 1987

Step 2: Find the prime factorization of 1991

1991 = 11 x 181

Step 3: Multiply each factor the greater number of times it occurs in steps i) or ii) above to find the lcm:

LCM = 3956117 = 11 x 181 x 1987

Step 4: Therefore, the least common multiple of 1987 and 1991 is 3956117.