Factor Calculator

Factors of 1161

The factors of 1161 are 1, 3, 9, 27, 43, 129, 387, and 1161. In total, 1161 has 8 factors. Its prime factorization is 3³ × 43, and the sum of all its factors is 1760.

All factors of 1161

Here are all 8 factors of 1161, listed from smallest to largest.

13927431293871161

Factor pairs of 1161

These 4 pairs of whole numbers each multiply to give 1161.

1 × 1161 = 1161
3 × 387 = 1161
9 × 129 = 1161
27 × 43 = 1161

Prime factorization of 1161

Dividing 1161 by the smallest prime at each step gives its prime factorization:

1161 ÷ 3 = 387
387 ÷ 3 = 129
129 ÷ 3 = 43
43 ÷ 43 = 1
Result: 1161 = 3 × 3 × 3 × 43 = 3³ × 43

The distinct prime factors of 1161 are 3, 43. To factorize any other number, use the prime factorization calculator.

Factor tree of 1161

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

Factor tree of 1161116133873129343
Prime factors are shown in solid indigo. Composite numbers split into their smallest prime and the quotient.

Properties of 1161

Number of factors8
Sum of factors1760
Sum of proper factors599
Prime factorization3³ × 43
Prime or composite?Composite
Even or odd?Odd
Perfect square?No
Perfect cube?No
ClassificationDeficient

What makes 1161 interesting

  • 1161 is a composite number, meaning it has more than two factors. It can be written as a product of smaller whole numbers in 4 different ways.
  • 1161 is a deficient number: its proper factors sum to 599, which is 562 less than 1161 itself.

How to find the factors of 1161 yourself

Divide 1161 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 √1161 ≈ 34.07, because every factor above that pairs with one below it.

1161 ÷ 1 = 1161 ✓
1161 ÷ 3 = 387 ✓
1161 ÷ 9 = 129 ✓
1161 ÷ 27 = 43 ✓

Reading both columns gives every factor: 1, 3, 9, 27, 43, 129, 387, 1161. The factor calculator does this automatically for any number.

Numbers mathematically connected to 1161.

Frequently asked questions about 1161

What are the factors of 1161?

The factors of 1161 are 1, 3, 9, 27, 43, 129, 387, and 1161. That is 8 factors in total, counting both 1 and 1161.

Is 1161 a prime number?

No, 1161 is not prime — it is a composite number with 8 factors. A prime number has exactly two factors, but 1161 is also divisible by 3.

What is the prime factorization of 1161?

The prime factorization of 1161 is 3³ × 43. Written out in full: 3 × 3 × 3 × 43 = 1161. Its distinct prime factors are 3, 43.

What two numbers multiply to give 1161?

There are 4 pairs of whole numbers that multiply to 1161: 1 × 1161, 3 × 387, 9 × 129, 27 × 43.

What is the sum of the factors of 1161?

Adding all the factors of 1161 together gives 1760. Excluding 1161 itself, the proper factors sum to 599.

Is 1161 a perfect square?

No, 1161 is not a perfect square. There is no whole number that multiplies by itself to give 1161. The nearest perfect squares are 1156 and 1225.

What is the largest factor of 1161 other than itself?

The largest factor of 1161 apart from 1161 itself is 387, since 1161 ÷ 387 = 3.

How many factors does 1161 have?

1161 has 8 factors: 1, 3, 9, 27, 43, 129, 387, and 1161. You can verify this from the prime factorization 3³ × 43: add 1 to each exponent and multiply, giving 4 × 2 = 8.

Explore more

Try another number in the factor calculator, break 1161 down further with the prime factorization calculator, or compare 1161 with another number using the GCF calculator and LCM calculator. For divisor counts and sums, see the divisor calculator.