Least Common Multiple  of 21 and 29 is 609

How to find the Least Common Multiple of 21 and 29?

On this page below, we'll use the Prime Factorisation, and the List of Multiples method to find out the LCM of 21 and 29.

Follow the steps below, and let's calculate the LCM of 21 and 29.


Method 1 - Prime factorization

Step 1: Create a list of all the prime factors of the numbers 21 and 29:

Prime factors of 21

The prime factors of 21 are 3 and 7. Prime factorization of 21 in exponential form is:

21 = 31x71

Prime factors of 29

The prime factors of 29 are 29. Prime factorization of 29 in exponential form is:

29 = 291


Step 2: Identify the highest power of each prime number from the above boxes:

31, 71, 291


Step 3: Multiply these values together:

31x71x291=609


Step 4: The result:

As seen on the calculation above, we have now obtained the LCM of 21 and 29.

The Least Common Multiple of 21 and 29 is 609.


Method 2 - List of Multiples

Find and list multiples of each number until the first common multiple is found. This is the lowest common multiple.


Multiples of 21:

21, 42, 63, 84, 105, 126, 147, 168, 189, 210, 231, 252, 273, 294, 315, 336, 357, 378, 399, 420, 441, 462, 483, 504, 525, 546, 567, 588, 609, 630, 651, 672

Multiples of 29:

29, 58, 87, 116, 145, 174, 203, 232, 261, 290, 319, 348, 377, 406, 435, 464, 493, 522, 551, 580, 609, 638, 667, 696


Therefore,

LCM(21, 29) = 609