remember
[tex](a^b)^c=a^{bc}[/tex]
note that if [tex]a^3[/tex] is a perfect cube then [tex](a^3)^c[/tex] is also a perfect cube when c is an integer
[tex](a^3)^c=a^{3c}[/tex]
so if a number is a perfect cube then the power must be divisible by 3
8 is not divisible by 3
24 is divisible by 3
26 is not divisibley by 3
64 is not divisible by 3
the perfect cube is y^24