Think you. I modified my source :
printf("%lu * %bu = ", N, M); printf("%lu\n", Freq); Freq=25690112L; printf("%lu * %bu = ", Freq, 4); Freq*=4; printf("%lu\n", Freq);
It work correctly. but the Long Integer Multiple fault also.
Run Result: 24500000 * 4 = 4294926936 25690112 * 4 = 1568