Factor Calculator

Factors of 243

The factors of 243 are 1, 3, 9, 27, 81, and 243. In total, 243 has 6 factors. Its prime factorization is 3⁵, and the sum of all its factors is 364.

All factors of 243

Here are all 6 factors of 243, listed from smallest to largest.

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Factor pairs of 243

These 3 pairs of whole numbers each multiply to give 243.

1 × 243 = 243
3 × 81 = 243
9 × 27 = 243

Prime factorization of 243

Dividing 243 by the smallest prime at each step gives its prime factorization:

243 ÷ 3 = 81
81 ÷ 3 = 27
27 ÷ 3 = 9
9 ÷ 3 = 3
3 ÷ 3 = 1
Result: 243 = 3 × 3 × 3 × 3 × 3 = 3⁵

The distinct prime factors of 243 are 3. To factorize any other number, use the prime factorization calculator.

Factor tree of 243

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

Factor tree of 2432433813273933
Prime factors are shown in solid indigo. Composite numbers split into their smallest prime and the quotient.

Properties of 243

Number of factors6
Sum of factors364
Sum of proper factors121
Prime factorization3⁵
Prime or composite?Composite
Even or odd?Odd
Perfect square?No
Perfect cube?No
ClassificationDeficient

What makes 243 interesting

  • 243 is a composite number, meaning it has more than two factors. It can be written as a product of smaller whole numbers in 3 different ways.
  • 243 is a deficient number: its proper factors sum to 121, which is 122 less than 243 itself.
  • 243 is a prime power: it is 3 raised to the power of 5. All of its factors are powers of 3.

How to find the factors of 243 yourself

Divide 243 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 √24315.59, because every factor above that pairs with one below it.

243 ÷ 1 = 243
243 ÷ 3 = 81
243 ÷ 9 = 27

Reading both columns gives every factor: 1, 3, 9, 27, 81, 243. The factor calculator does this automatically for any number.

Frequently asked questions about 243

What are the factors of 243?

The factors of 243 are 1, 3, 9, 27, 81, and 243. That is 6 factors in total, counting both 1 and 243.

Is 243 a prime number?

No, 243 is not prime — it is a composite number with 6 factors. A prime number has exactly two factors, but 243 is also divisible by 3.

What is the prime factorization of 243?

The prime factorization of 243 is 3⁵. Written out in full: 3 × 3 × 3 × 3 × 3 = 243. Its distinct prime factors are 3.

What two numbers multiply to give 243?

There are 3 pairs of whole numbers that multiply to 243: 1 × 243, 3 × 81, 9 × 27.

What is the sum of the factors of 243?

Adding all the factors of 243 together gives 364. Excluding 243 itself, the proper factors sum to 121.

Is 243 a perfect square?

No, 243 is not a perfect square. There is no whole number that multiplies by itself to give 243. The nearest perfect squares are 225 and 256.

What is the largest factor of 243 other than itself?

The largest factor of 243 apart from 243 itself is 81, since 243 ÷ 81 = 3.

How many factors does 243 have?

243 has 6 factors: 1, 3, 9, 27, 81, and 243. You can verify this from the prime factorization 3⁵: add 1 to each exponent and multiply, giving 6 = 6.

Explore more

Try another number in the factor calculator, break 243 down further with the prime factorization calculator, or compare 243 with another number using the GCF calculator and LCM calculator. For divisor counts and sums, see the divisor calculator.