Identify the Powerful Numbers from the following

Powerful numbers are positive integers where every prime factor appears with at least exponent 2 (they can be expressed as m^2 * n^3). 729 = 3^6 (all prime factors have exponent >=2) and 512 = 2^9 are powerful numbers. 423 = 3 x 141 and 372 = 2^2 x 3 x 31 are not powerful because they have prime factors (3 and 31) with exponent 1.