What is the Least Common Multiple of 3991 and 4004?

Least common multiple or lowest common denominator (lcd) can be calculated in two way; with the LCM formula calculation of greatest common factor (GCF), or multiplying the prime factors with the highest exponent factor.

Least Common Multiple of 3991 and 4004 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 3991 and 4004, than apply into the LCM equation.

GCF(3991,4004) = 13
LCM(3991,4004) = ( 3991 × 4004) / 13
LCM(3991,4004) = 15979964 / 13
LCM(3991,4004) = 1229228

Least Common Multiple (LCM) of 3991 and 4004 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 3991 and 4004. First we will calculate the prime factors of 3991 and 4004.

Prime Factorization of 3991

Prime Factorization of 4004

Now multiplying the highest exponent prime factors to calculate the LCM of 3991 and 4004.

LCM(3991,4004) = 13¹ × 307¹ × 2² × 7¹ × 11¹
LCM(3991,4004) = 1229228