Since the volume is the cube of the side:
[tex]V=s^3[/tex]
the inverse formula is
[tex]s=\sqrt[3]{V}=\sqrt[3]{125}=5[/tex]
So, our cube has side length 5. Since a cube is composed of 6 squares, the surface area is 6 times the area of a square of side 5, i.e.
[tex]6s^2=6\cdot 5^2 = 6\cdot 25=150[/tex]