What is the Least Common Multiple of 9991 and 9999?

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 9991 and 9999 with GCF Formula

The formula of LCM is LCM(a,b) = ( a × b) / GCF(a,b).
We need to calculate greatest common factor 9991 and 9999, than apply into the LCM equation.

GCF(9991,9999) = 1
LCM(9991,9999) = ( 9991 × 9999) / 1
LCM(9991,9999) = 99900009 / 1
LCM(9991,9999) = 99900009

Least Common Multiple (LCM) of 9991 and 9999 with Primes

Least common multiple can be found by multiplying the highest exponent prime factors of 9991 and 9999. First we will calculate the prime factors of 9991 and 9999.

Prime Factorization of 9991

Prime Factorization of 9999

Now multiplying the highest exponent prime factors to calculate the LCM of 9991 and 9999.

LCM(9991,9999) = 97¹ × 103¹ × 3² × 11¹ × 101¹
LCM(9991,9999) = 99900009