10101 base 2 = 21 base 10 126 is an illegal base 5 number A4C base 15 = 1821 base 11 a4C is an illegal base 15 number zyC is an illegal base 15 number 253 base 10 = FD base 16 %^&%^&%^& is an illegal base 10 number FFFFFFFFFF base 16 = 1099511627775 base 10 FFFFFFFFFF base 16 = FFFFFFFFFF base 16 FFFFFFFFFF base 16 = 1111111111111111111111111111111111111111 base 2 1821 base 11 = A4C base 15 0 base 16 = 0 base 2 0 base 2 = 0 base 16 00F base 16 = 1111 base 2 0010 base 2 = 2 base 16 AA base 11 = 11110 base 3 AB is an illegal base 11 number