Let us try with the prime facotrisation.

What is 8 cubed? What is 5 cubed? What is the difference?

Can we calculate the volume of cuboid? How many such cuboids are required to make a cube?

Well, we can try this also by working out the digits only at the ones place instead of solving the whole problem.

Can we write all the factors as power of 3?

Think about the multiplication of number by itself three times.

What is the definition of a cubed number?

What is 7 cubed? What is 6 cubed? What is the difference?

Can we write all the factors as power of 3?

Think about numbers that do not have a pair in the prime factorisation?