LCM for 21 and 100

What's the Least Common Multiple (LCM) of 21 and 100?

Answer: LCM of 21 and 100 is 2,100

(Two thousand, one hundred)

Finding LCM for 21 and 100 using GCF's of these numbers

The first method to find LCM for numbers 21 and 100 is to find Greatest Common Factor (GCF) of these numbers. Here's the formula:

LCM = (Number1 × Number2) ÷ GCF

GCF of numbers 21 and 100 is 1, so

LCM = (21 × 100) ÷ 1

LCM = 2100 ÷ 1

LCM = 2100

Finding LCM for 21 and 100 by Listing Multiples

The second method to find LCM for numbers 21 and 100 is to list out the common multiples for both nubmers and pick the first which matching:

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, 693, 714, 735, 756, 777, 798, 819, 840, 861, 882, 903, 924, 945, 966, 987, 1008, 1029, 1050, 1071, 1092, 1113, 1134, 1155, 1176, 1197, 1218, 1239, 1260, 1281, 1302, 1323, 1344, 1365, 1386, 1407, 1428, 1449, 1470, 1491, 1512, 1533, 1554, 1575, 1596, 1617, 1638, 1659, 1680, 1701, 1722, 1743, 1764, 1785, 1806, 1827, 1848, 1869, 1890, 1911, 1932, 1953, 1974, 1995, 2016, 2037, 2058, 2079, 2100, 2121, 2142

Multiples of 100: 100, 200, 300, 400, 500, 600, 700, 800, 900, 1000, 1100, 1200, 1300, 1400, 1500, 1600, 1700, 1800, 1900, 2000, 2100, 2200, 2300

So the LCM for 21 and 100 is 2100

Finding LCM for 21 and 100 by Prime Factorization

Another method to find LCM for numbers 21 and 100 is to list all Prime Factors for both numbers and multiply the highest exponent prime factors:

All Prime Factors of 21: 3, 7 (exponent form: 31, 71)

All Prime Factors of 100: 2, 2, 5, 5 (exponent form: 22, 52)

31 × 71 × 22 × 52 = 2100

See Also

About "Least Common Multiple" Calculator

This calculator will help you find the Least Common Multiple (LCM) of two numbers. For example, it can help you find out what's the Least Common Multiple (LCM) of 21 and 100? (The answer is: 2100). Select the first number (e.g. '21') and the second number (e.g. '100'). After that hit the 'Calculate' button.
Least Common Multiple (LCM) also known as the Lowest Common Multiple or Smallest Common Multiple of 2 numbers - it is the smallest positive integer that is divisible by both numbers

LCM Table

Number 1Number 2LCM
6100
7100
8100
9100
10100100
111001100
12100
131001300
14100700
15100
16100400
171001700
18100900
191001900
20100
21100
221001100
231002300
24100600
25100
261001300
271002700
28100700
291002900
30100300
311003100
32100800
331003300
341001700
35100700

FAQ

What's the Least Common Multiple (LCM) of 21 and 100?

LCM of 21 and 100 is 2,100