Factors of 11

11 has 2 factors: 1 and 11. Its prime factorization is 11.

Factor pairs of 11

Factor×FactorProduct
1×1111

Negative pairs work too: (−1) × (−11) = 11.

Number of factors
2
Factor pairs
1
Sum of factors
12
Prime or composite
Prime
Even or odd
Odd
Perfect square
No
Prime factorization 11

How to find the factors of 11

Test every whole number from 1 up to the square root of 11 (√11 ≈ 3.317). Each number that divides evenly gives you two factors at once: the divisor and the quotient.

  • 11 ÷ 1 = 11 — so 1 and 11 are factors
  • 11 ÷ 2 = 5.5 — not a whole number
  • 11 ÷ 3 = 3.667 — not a whole number

Collecting both numbers from every successful division gives the complete list: 1 and 11.

Prime factorization of 11

11 is a prime number, so it cannot be broken down any further. Its prime factorization is simply 11.

Properties of 11

  • 11 is a prime number.
  • The sum of all its factors is 12; the sum of its proper factors (excluding 11) is 1, which makes it a deficient number (its proper factors add up to less than itself).
  • 11 is not a perfect square, so its factors pair up evenly.
  • Multiples of 11 include 22, 33, 44, 55 and so on.

Factors vs. multiples

Factors of 11 are the numbers that divide into it; multiples of 11 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 11?

The factors of 11 are 1 and 11. Each of these divides 11 with no remainder.

How many factors does 11 have?

11 has 2 positive factors, which form 1 factor pair. Counting negative factors as well doubles that to 4.

What is the prime factorization of 11?

11 = 11. 11 is prime, so it is its own prime factorization.

Is 11 a prime number?

Yes. 11 is prime because its only factors are 1 and 11.