Given a positive number x:
p = (p1, p2, …)
// Set of *prime* factors of x
If the square of every item in p is also a factor of x, then x is said to be a powerful number.
Create a function that takes a number and returns true if it's powerful, false if it's not.
isPowerful(36) ➞ true
// p = (2, 3) (prime factors of 36)
// 2^2 = 4 (factor of 36)
// 3^2 = 9 (factor of 36)
isPowerful(27) ➞ true
isPowerful(674) ➞ false
N/A