cubes and cube roots math is fun maths resources cube root a cube root goes the other direction 3 cubed is 27 so the cube root of 27 is 3 cube algebra a cube number or a perfect cube or sometimes just a cube is a number which is the cube of an integer the perfect cubes up to 60 3 are cube math word definition math open reference face also called facets or sides a cube has six faces which are all squares so each face has four equal sides and all four interior angles are right angles