Factors of 78

How to find the factors of 78

Test every whole number from 1 up to the square root of 78 (√78 ≈ 8.832). Each number that divides evenly gives you two factors at once: the divisor and the quotient.

• 78 ÷ 1 = 78 — so 1 and 78 are factors
• 78 ÷ 2 = 39 — so 2 and 39 are factors
• 78 ÷ 3 = 26 — so 3 and 26 are factors
• 78 ÷ 4 = 19.5 — not a whole number
• 78 ÷ 5 = 15.6 — not a whole number
• 78 ÷ 6 = 13 — so 6 and 13 are factors
• 78 ÷ 7 = 11.143 — not a whole number
• 78 ÷ 8 = 9.75 — not a whole number

Collecting both numbers from every successful division gives the complete list: 1, 2, 3, 6, 13, 26, 39 and 78.

Prime factorization of 78

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

The primes you divided by give 78 = 2 × 3 × 13. From the exponents you can also count the factors without listing them: (1 + 1) × (1 + 1) × (1 + 1) = 8.

Properties of 78

• 78 is a composite number.
• The sum of all its factors is 168; the sum of its proper factors (excluding 78) is 90, which makes it a abundant number (its proper factors add up to more than itself).
• 78 is not a perfect square, so its factors pair up evenly.
• Multiples of 78 include 156, 234, 312, 390 and so on.

Factors vs. multiples

Factors of 78 are the numbers that divide into it; multiples of 78 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.