Factors of 345

345 has 8 factors: 1, 3, 5, 15, 23, 69, 115 and 345. Its prime factorization is 3 × 5 × 23.

Factor pairs of 345

Factor×FactorProduct
1×345345
3×115345
5×69345
15×23345

Negative pairs work too: (−1) × (−345), (−3) × (−115), … = 345.

Number of factors
8
Factor pairs
4
Sum of factors
576
Prime or composite
Composite
Even or odd
Odd
Perfect square
No
Prime factorization 3 × 5 × 23

How to find the factors of 345

Test every whole number from 1 up to the square root of 345 (√345 ≈ 18.574). Each number that divides evenly gives you two factors at once: the divisor and the quotient.

  • 345 ÷ 1 = 345 — so 1 and 345 are factors
  • 345 ÷ 2 = 172.5 — not a whole number
  • 345 ÷ 3 = 115 — so 3 and 115 are factors
  • 345 ÷ 4 = 86.25 — not a whole number
  • 345 ÷ 5 = 69 — so 5 and 69 are factors
  • 345 ÷ 6 = 57.5 — not a whole number
  • 345 ÷ 7 = 49.286 — not a whole number
  • 345 ÷ 8 = 43.125 — not a whole number
  • 345 ÷ 9 = 38.333 — not a whole number
  • 345 ÷ 10 = 34.5 — not a whole number
  • 345 ÷ 11 = 31.364 — not a whole number
  • 345 ÷ 12 = 28.75 — not a whole number
  • 345 ÷ 13 = 26.538 — not a whole number
  • 345 ÷ 14 = 24.643 — not a whole number
  • 345 ÷ 15 = 23 — so 15 and 23 are factors
  • 345 ÷ 16 = 21.563 — not a whole number
  • 345 ÷ 17 = 20.294 — not a whole number
  • 345 ÷ 18 = 19.167 — not a whole number

Collecting both numbers from every successful division gives the complete list: 1, 3, 5, 15, 23, 69, 115 and 345.

Prime factorization of 345

Divide by the smallest prime that fits, and keep going until the quotient is 1:

345 ÷ 3 = 115
115 ÷ 5 = 23
23 ÷ 23 = 1

The primes you divided by give 345 = 3 × 5 × 23. From the exponents you can also count the factors without listing them: (1 + 1) × (1 + 1) × (1 + 1) = 8.

Properties of 345

  • 345 is a composite number.
  • The sum of all its factors is 576; the sum of its proper factors (excluding 345) is 231, which makes it a deficient number (its proper factors add up to less than itself).
  • 345 is not a perfect square, so its factors pair up evenly.
  • Multiples of 345 include 690, 1,035, 1,380, 1,725 and so on.

Factors vs. multiples

Factors of 345 are the numbers that divide into it; multiples of 345 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 345?

The factors of 345 are 1, 3, 5, 15, 23, 69, 115 and 345. Each of these divides 345 with no remainder.

How many factors does 345 have?

345 has 8 positive factors, which form 4 factor pairs. Counting negative factors as well doubles that to 16.

What is the prime factorization of 345?

345 = 3 × 5 × 23. Its distinct prime factors are 3, 5 and 23.

Is 345 a prime number?

No. 345 is composite because it has 8 factors, more than the two a prime number has.