Is 225 a prime number?

No, 225 is composite. It is divisible by 3, 5, 9, 15, 25, 45 and 75.

Factors of 225

The factors of 225 are 1, 3, 5, 9, 15, 25, 45, 75 and 225. That is 9 factors in total.

A factor of 225 is a whole number that divides 225 exactly, with no remainder. 225 is a composite number because it has factors other than 1 and itself.

Factor pairs of 225

Two numbers that multiply to give 225:

1 × 225 = 225
3 × 75 = 225
5 × 45 = 225
9 × 25 = 225
15 × 15 = 225

Prime factorization of 225

225 = 3 × 3 × 5 × 5 = 3² × 5². The prime factors of 225 are 3 and 5.

Quick facts about 225

Is 225 prime? No.
Even or odd: odd.
Sum of its factors: 1 + 3 + 5 + 9 + 15 + 25 + 45 + 75 + 225 = 403.
225 is a perfect square (15 × 15), so it has an odd number of factors.

Factors of nearby numbers

Number	Factors
197	1, 197
198	1, 2, 3, 6, 9, 11, 18, 22, 33, 66, 99, 198
199	1, 199
200	1, 2, 4, 5, 8, 10, 20, 25, 40, 50, 100, 200
240	20 factors
250	1, 2, 5, 10, 25, 50, 125, 250
256	1, 2, 4, 8, 16, 32, 64, 128, 256
300	18 factors

More about 225: square root of 225 · 225 in binary.

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