What is the Least Common Multiple of 19991 and 19999?

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 19991 and 19999 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 19991 and 19999, than apply into the LCM equation.

GCF(19991,19999) = 1
LCM(19991,19999) = ( 19991 × 19999) / 1
LCM(19991,19999) = 399800009 / 1
LCM(19991,19999) = 399800009

Least Common Multiple (LCM) of 19991 and 19999 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 19991 and 19999. First we will calculate the prime factors of 19991 and 19999.

Prime Factorization of 19991

Prime Factorization of 19999

Now multiplying the highest exponent prime factors to calculate the LCM of 19991 and 19999.

LCM(19991,19999) = 19991¹ × 7¹ × 2857¹
LCM(19991,19999) = 399800009