How to find the factors of 289
Test every whole number from 1 up to the square root of 289 (√289 ≈ 17.000). Each number that divides evenly gives you two factors at once: the divisor and the quotient.
- 289 ÷ 1 = 289 — so 1 and 289 are factors
- 289 ÷ 2 = 144.5 — not a whole number
- 289 ÷ 3 = 96.333 — not a whole number
- 289 ÷ 4 = 72.25 — not a whole number
- 289 ÷ 5 = 57.8 — not a whole number
- 289 ÷ 6 = 48.167 — not a whole number
- 289 ÷ 7 = 41.286 — not a whole number
- 289 ÷ 8 = 36.125 — not a whole number
- 289 ÷ 9 = 32.111 — not a whole number
- 289 ÷ 10 = 28.9 — not a whole number
- 289 ÷ 11 = 26.273 — not a whole number
- 289 ÷ 12 = 24.083 — not a whole number
- 289 ÷ 13 = 22.231 — not a whole number
- 289 ÷ 14 = 20.643 — not a whole number
- 289 ÷ 15 = 19.267 — not a whole number
- 289 ÷ 16 = 18.063 — not a whole number
- 289 ÷ 17 = 17 — so 17 and 17 are factors
Collecting both numbers from every successful division gives the complete list: 1, 17 and 289.
Prime factorization of 289
Divide by the smallest prime that fits, and keep going until the quotient is 1:
The primes you divided by give 289 = 17². From the exponents you can also count the factors without listing them: (2 + 1) = 3.
Properties of 289
- 289 is a composite number.
- The sum of all its factors is 307; the sum of its proper factors (excluding 289) is 18, which makes it a deficient number (its proper factors add up to less than itself).
- 289 is a perfect square: 17 × 17. Perfect squares always have an odd number of factors.
- Multiples of 289 include 578, 867, 1,156, 1,445 and so on.
Factors vs. multiples
Factors of 289 are the numbers that divide into it; multiples of 289 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 289?
The factors of 289 are 1, 17 and 289. Each of these divides 289 with no remainder.
How many factors does 289 have?
289 has 3 positive factors, which form 2 factor pairs. Counting negative factors as well doubles that to 6.
What is the prime factorization of 289?
289 = 17². Its distinct prime factors are 17.
Is 289 a prime number?
No. 289 is composite because it has 3 factors, more than the two a prime number has.