The result of multiplying a whole number by itself twice.
Example: 3 × 3 × 3 = 27, so 27 is a cube number.
The whole number is used three times, just like the sides of a cube.
Here are the first few cube numbers:
1 (=1×1×1)
8 (=2×2×2)
27 (=3×3×3)
64 (=4×4×4)
125 (=5×5×5)
... etc
See: Square Number