ClearAll[RhondaNumberQ] RhondaNumberQ[b_Integer][n_Integer] := Module[{l, r}, l = Times @@ IntegerDigits[n, b]; r = Total[Catenate[ConstantArray @@@ FactorInteger[n]]]; l == b r ] bases = Select[Range[2, 36], PrimeQ/*Not]; Do[ Print["base ", b, ":", Take[Select[Range[700000], RhondaNumberQ[b]], UpTo[15]]]; , {b, bases} ]