How to find the factors of 231
Test every whole number from 1 up to the square root of 231 (√231 ≈ 15.199). Each number that divides evenly gives you two factors at once: the divisor and the quotient.
- 231 ÷ 1 = 231 — so 1 and 231 are factors
- 231 ÷ 2 = 115.5 — not a whole number
- 231 ÷ 3 = 77 — so 3 and 77 are factors
- 231 ÷ 4 = 57.75 — not a whole number
- 231 ÷ 5 = 46.2 — not a whole number
- 231 ÷ 6 = 38.5 — not a whole number
- 231 ÷ 7 = 33 — so 7 and 33 are factors
- 231 ÷ 8 = 28.875 — not a whole number
- 231 ÷ 9 = 25.667 — not a whole number
- 231 ÷ 10 = 23.1 — not a whole number
- 231 ÷ 11 = 21 — so 11 and 21 are factors
- 231 ÷ 12 = 19.25 — not a whole number
- 231 ÷ 13 = 17.769 — not a whole number
- 231 ÷ 14 = 16.5 — not a whole number
- 231 ÷ 15 = 15.4 — not a whole number
Collecting both numbers from every successful division gives the complete list: 1, 3, 7, 11, 21, 33, 77 and 231.
Prime factorization of 231
Divide by the smallest prime that fits, and keep going until the quotient is 1:
The primes you divided by give 231 = 3 × 7 × 11. From the exponents you can also count the factors without listing them: (1 + 1) × (1 + 1) × (1 + 1) = 8.
Properties of 231
- 231 is a composite number.
- The sum of all its factors is 384; the sum of its proper factors (excluding 231) is 153, which makes it a deficient number (its proper factors add up to less than itself).
- 231 is not a perfect square, so its factors pair up evenly.
- Multiples of 231 include 462, 693, 924, 1,155 and so on.
Factors vs. multiples
Factors of 231 are the numbers that divide into it; multiples of 231 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 231?
The factors of 231 are 1, 3, 7, 11, 21, 33, 77 and 231. Each of these divides 231 with no remainder.
How many factors does 231 have?
231 has 8 positive factors, which form 4 factor pairs. Counting negative factors as well doubles that to 16.
What is the prime factorization of 231?
231 = 3 × 7 × 11. Its distinct prime factors are 3, 7 and 11.
Is 231 a prime number?
No. 231 is composite because it has 8 factors, more than the two a prime number has.