Calculate the least common multiple of numbers, LCM

Online calculator: LCM, the least common multiple

Calculate the least common multiple of numbers, LCM:

Approach 1: Integer numbers prime factorization, multiply all the prime factors, by the largest exponents.

Approach 2: Euclid's algorithm:
lcm (a; b) = (a × b) / gcf, hcf, gcd (a; b).

Approach 3: Integer numbers divisibility.

Latest calculated least common multiples, LCM

Tutoring: what is it and how to calculate the least common multiple LCM of integer numbers

60 is a common multiple of the numbers 6 and 15, because 60 is a multiple of 6 and is also a multiple of 15. But there is also an infinite number of common multiples of 6 and 15.

If "v" is a multiple of "a" and "b", then all the multiples of "v" are also multiples of "a" and "b".

Common multiples of 6 and 15 are: 30, 60, 90, 120... Among them, 30 is the lowest and we say that 30 is the least common multiple, or the lowest common multiple, or the smallest common multiple of 6 and 15, abbreviated as LCM.

If e = LCM (a; b), then "e" contains all the prime factors involved in the prime factorizations of both "a" and "b", by the highest powers (exponents).

Based on this rule we can calculate the least common multiple, LCM, of the three numbers in the example below:

  • 40 = 23 × 5
  • 36 = 22 × 32
  • 126 = 2 × 32 × 7
  • LCM (40; 36; 126) = 23 × 32 × 5 × 7 = 2,520

What is a prime number?

What is a composite number?

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Sieve of Eratosthenes

Euclid's algorithm

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