Write a program that, given a natural number , determines the smallest natural number whose cube is a multiple of .
A single natural number .
Print a single natural number — the smallest positive integer whose cube (third power) is divisible by without a remainder.
Example 1
For example, neither 1^3 = 1, nor 2^3 = 8, nor 3^3 = 27, nor 4^3 = 64, nor 5^3 = 125 are divisible by without a remainder, but 6^3 = 216 is divisible. Thus, 6^3 is the smallest natural cube that is a multiple of .
of the points are for tests where 2 \leq k \leq 100;
of the points for 10^5 < k < 10^6;
of the points for 10^7 < k < 10^8;
of the points for 10^{10} < k < 10^{12};
of the points for 10^{15} < k < 10^{18}.
You need to write a single program that handles all these cases efficiently. The breakdown of constraints is provided to indicate how points are distributed based on the efficiency of your solution.