What is a perfect cube?
A perfect cube is a number that can be expressed as the product of an integer multiplied by itself three times. In other words, N is a perfect cube if N = a × a × a for some integer a. Examples include 1, 8, 27, 64, and 125. See also our Factorial Calculator.
How do I check if a number is a perfect cube?
To check if a number N is a perfect cube, calculate its cube root (∛N). If the cube root is an integer (a whole number with no decimal part), then N is a perfect cube. For example, ∛64 = 4, which is an integer, so 64 is a perfect cube.
Can the cube root of a number be negative?
Yes! Unlike square roots, cube roots can be negative. For example, the cube root of -8 is -2, because (-2) × (-2) × (-2) = -8. So negative numbers can also be perfect cubes.
Is 64 a perfect cube?
Yes, 64 is a perfect cube. Its cube root is 4, since 4 × 4 × 4 = 64. It is also a perfect square (8²), making it one of the few numbers that are both a perfect square and a perfect cube.
Is 27 a perfect cube?
Yes, 27 is a perfect cube. The cube root of 27 is 3, because 3 × 3 × 3 = 27.
Which numbers are perfect cubes?
Perfect cubes are numbers like 1, 8, 27, 64, 125, 216, 343, 512, 729, 1000, and so on — formed by cubing integers 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, etc. Negative perfect cubes include -1, -8, -27, -64, and so on.
Is 1 a perfect cube?
Yes, 1 is a perfect cube because 1 × 1 × 1 = 1. The cube root of 1 is 1, which is an integer, confirming it as a perfect cube.