GCF for 4, 18 and 24

"Greatest Common Factor of 3 Numbers" Calculator
Greatest Common Factor of
,
and

What's the Greatest Common Factor (GCF) of 4, 18 and 24?

Answer

GCF of 4, 18 and 24 is
2

(Two)

2 is the largest positive integer that divides 4, 18 and 24 without a remainder — every other common divisor of the three divides it too.

Finding the GCF of 4, 18 and 24 by Prime Factorization

Split all three numbers into prime factors, then keep every prime that appears in all three of them, each taken as many times as it appears in the poorest factorization. Multiplying what is left gives the greatest common factor:

All Prime Factors of 4: 2 × 2 (exponent form: 22)

All Prime Factors of 18: 2 × 3 × 3 (exponent form: 2 × 32)

All Prime Factors of 24: 2 × 2 × 2 × 3 (exponent form: 23 × 3)

Prime factor41824Lowest power
2222232
3—323—

GCF = 2 = 2

Checking the GCF of 4, 18 and 24 Two Numbers at a Time

The greatest common factor is associative, so three numbers can be handled as two pairs — and this is what makes the Euclidean algorithm usable here: run it on the first pair, then run it again on that result and the third number.

GCF(a, b, c) = GCF(GCF(a, b), c)

GCF(4, 18) = 2

GCF(2, 24) = 2

GCF(4, 18, 24) = 2

The answer checks out by division — all three quotients come out whole:

4 ÷ 2 = 2

18 ÷ 2 = 9

24 ÷ 2 = 12

2, 9 and 12 have no common factor left — that is what makes 2 the greatest one.

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See Also

About "Greatest Common Factor of 3 Numbers" Calculator

This calculator finds the Greatest Common Factor (GCF) of three numbers at once, without doing it in two passes. For example, it can help you find out what's the Greatest Common Factor (GCF) of 4, 18 and 24? (The answer is: 2). Enter the first number (e.g. '4'), the second (e.g. '18') and the third (e.g. '24'), then hit the 'Calculate' button.
The Greatest Common Factor of three numbers — also called the greatest common divisor (GCD) or highest common factor (HCF) — is the largest positive integer that divides all three of them with zero remainder
"Greatest Common Factor of 3 Numbers" Calculator
Greatest Common Factor of
,
and

GCF Table

Number 1Number 2Number 3GCF
49181
410182
411181
412182
413181
414182
415181
416182
417181
418182
418191
418202
418211
418222
418231
418242
418251
418262
418271
418282
418291
418302
418311
418322
418331
418342
418351
418362
418371
418382

FAQ

What's the Greatest Common Factor (GCF) of 4, 18 and 24?

GCF of 4, 18 and 24 is 2

What prime factors do 4, 18 and 24 share?

All three factorizations contain 2, and multiplying those shared primes gives 2 — exactly the greatest common factor.

Can you get the GCF of 4, 18 and 24 two numbers at a time?

Yes, and it is the check this page prints. The GCF of 4 and 18 is 2, and the GCF of 2 and 24 is 2 — the same answer, because the greatest common factor is associative and does not depend on the order of the three numbers.

How does the GCF simplify the ratio 4 : 18 : 24?

Divide every term by the GCF 2: 4 ÷ 2 = 2, 18 ÷ 2 = 9 and 24 ÷ 2 = 12. So 4 : 18 : 24 in lowest terms is 2 : 9 : 12, and no whole number other than 1 divides all three of those.

See Also