How to find the factors of 945
Test every whole number from 1 up to the square root of 945 (√945 ≈ 30.741). Each number that divides evenly gives you two factors at once: the divisor and the quotient.
- 945 ÷ 1 = 945 — so 1 and 945 are factors
- 945 ÷ 2 = 472.5 — not a whole number
- 945 ÷ 3 = 315 — so 3 and 315 are factors
- 945 ÷ 4 = 236.25 — not a whole number
- 945 ÷ 5 = 189 — so 5 and 189 are factors
- 945 ÷ 6 = 157.5 — not a whole number
- 945 ÷ 7 = 135 — so 7 and 135 are factors
- 945 ÷ 8 = 118.125 — not a whole number
- 945 ÷ 9 = 105 — so 9 and 105 are factors
- 945 ÷ 10 = 94.5 — not a whole number
- 945 ÷ 11 = 85.909 — not a whole number
- 945 ÷ 12 = 78.75 — not a whole number
- 945 ÷ 13 = 72.692 — not a whole number
- 945 ÷ 14 = 67.5 — not a whole number
- 945 ÷ 15 = 63 — so 15 and 63 are factors
- 945 ÷ 16 = 59.063 — not a whole number
- 945 ÷ 17 = 55.588 — not a whole number
- 945 ÷ 18 = 52.5 — not a whole number
- 945 ÷ 19 = 49.737 — not a whole number
- 945 ÷ 20 = 47.25 — not a whole number
- 945 ÷ 21 = 45 — so 21 and 45 are factors
- 945 ÷ 22 = 42.955 — not a whole number
- 945 ÷ 23 = 41.087 — not a whole number
- 945 ÷ 24 = 39.375 — not a whole number
- 945 ÷ 25 = 37.8 — not a whole number
- 945 ÷ 26 = 36.346 — not a whole number
- 945 ÷ 27 = 35 — so 27 and 35 are factors
- 945 ÷ 28 = 33.75 — not a whole number
- 945 ÷ 29 = 32.586 — not a whole number
- 945 ÷ 30 = 31.5 — not a whole number
Collecting both numbers from every successful division gives the complete list: 1, 3, 5, 7, 9, 15, 21, 27, 35, 45, 63, 105, 135, 189, 315 and 945.
Prime factorization of 945
Divide by the smallest prime that fits, and keep going until the quotient is 1:
The primes you divided by give 945 = 3³ × 5 × 7. From the exponents you can also count the factors without listing them: (3 + 1) × (1 + 1) × (1 + 1) = 16.
Properties of 945
- 945 is a composite number.
- The sum of all its factors is 1,920; the sum of its proper factors (excluding 945) is 975, which makes it a abundant number (its proper factors add up to more than itself).
- 945 is not a perfect square, so its factors pair up evenly.
- Multiples of 945 include 1,890, 2,835, 3,780, 4,725 and so on.
Factors vs. multiples
Factors of 945 are the numbers that divide into it; multiples of 945 are the numbers it divides into. Every number has a limited set of factors but infinitely many multiples. To work with any other number, use the factors calculator, or find shared factors with the GCF calculator.
Frequently asked questions
What are the factors of 945?
The factors of 945 are 1, 3, 5, 7, 9, 15, 21, 27, 35, 45, 63, 105, 135, 189, 315 and 945. Each of these divides 945 with no remainder.
How many factors does 945 have?
945 has 16 positive factors, which form 8 factor pairs. Counting negative factors as well doubles that to 32.
What is the prime factorization of 945?
945 = 3³ × 5 × 7. Its distinct prime factors are 3, 5 and 7.
Is 945 a prime number?
No. 945 is composite because it has 16 factors, more than the two a prime number has.