Factor Calculator

Factors of 65

The factors of 65 are 1, 5, 13, and 65. In total, 65 has 4 factors. Its prime factorization is 5 × 13, and the sum of all its factors is 84.

All factors of 65

Here are all 4 factors of 65, listed from smallest to largest.

151365

Factor pairs of 65

These 2 pairs of whole numbers each multiply to give 65.

1 × 65 = 65
5 × 13 = 65

Prime factorization of 65

Dividing 65 by the smallest prime at each step gives its prime factorization:

65 ÷ 5 = 13
13 ÷ 13 = 1
Result: 65 = 5 × 13 = 5 × 13

The distinct prime factors of 65 are 5, 13. To factorize any other number, use the prime factorization calculator.

Factor tree of 65

A factor tree shows the same prime factorization visually. Each composite branch splits until every endpoint is a prime number.

Factor tree of 6565513
Prime factors are shown in solid indigo. Composite numbers split into their smallest prime and the quotient.

Properties of 65

Number of factors4
Sum of factors84
Sum of proper factors19
Prime factorization5 × 13
Prime or composite?Composite
Even or odd?Odd
Perfect square?No
Perfect cube?No
ClassificationDeficient

What makes 65 interesting

  • 65 is a composite number, meaning it has more than two factors. It can be written as a product of smaller whole numbers in 2 different ways.
  • 65 is a deficient number: its proper factors sum to 19, which is 46 less than 65 itself.

How to find the factors of 65 yourself

Divide 65 by each whole number starting from 1. Whenever the division leaves no remainder, both the divisor and the quotient are factors. You only need to test up to √65 ≈ 8.06, because every factor above that pairs with one below it.

65 ÷ 1 = 65 ✓
65 ÷ 5 = 13 ✓

Reading both columns gives every factor: 1, 5, 13, 65. The factor calculator does this automatically for any number.

Numbers mathematically connected to 65.

Frequently asked questions about 65

What are the factors of 65?

The factors of 65 are 1, 5, 13, and 65. That is 4 factors in total, counting both 1 and 65.

Is 65 a prime number?

No, 65 is not prime — it is a composite number with 4 factors. A prime number has exactly two factors, but 65 is also divisible by 5.

What is the prime factorization of 65?

The prime factorization of 65 is 5 × 13. Written out in full: 5 × 13 = 65. Its distinct prime factors are 5, 13.

What two numbers multiply to give 65?

There are 2 pairs of whole numbers that multiply to 65: 1 × 65, 5 × 13.

What is the sum of the factors of 65?

Adding all the factors of 65 together gives 84. Excluding 65 itself, the proper factors sum to 19.

Is 65 a perfect square?

No, 65 is not a perfect square. There is no whole number that multiplies by itself to give 65. The nearest perfect squares are 64 and 81.

What is the largest factor of 65 other than itself?

The largest factor of 65 apart from 65 itself is 13, since 65 ÷ 13 = 5.

How many factors does 65 have?

65 has 4 factors: 1, 5, 13, and 65. You can verify this from the prime factorization 5 × 13: add 1 to each exponent and multiply, giving 2 × 2 = 4.

Explore more

Try another number in the factor calculator, break 65 down further with the prime factorization calculator, or compare 65 with another number using the GCF calculator and LCM calculator. For divisor counts and sums, see the divisor calculator.