Help with defining variables

Hello everyone, I need some help with working with hexadecimal variables in C. I don't know exactly what is going wrong, as the program runs without an error, but I need to input a 16 digit hexadecimal number into the program, and then separate the digits 2 at a time. The problem is that it successfully separates the 8 digits to the right, but then for whatever reason, the left 8 digits aren't even defined int the variable. Here is my code for reference:

Code:

---

#include <stdio.h>
#include <stdlib.h>
#include <stdint.h>


int main(void) {
    int i, j;
    int m = 0;
    unsigned long int hexedit;
    unsigned long int hex = 0x10387cfe38383800;


    printf("%lx\n", hex);


    for (i = 1; i <= 8; i++) {
        hexedit = ((hex >> m) &0xff);  // shifts digits and                                                                            separates 2 digits
        printf("%lx ", hexedit);
        m += 8;
    }


    return EXIT_SUCCESS;
}

---

My output is below as well:

38383800
0 38 38 38 0 38 38 38

The last 4 outputs should be the last 8 digits of the input from right to left, but instead, it's just repeating the correct 4 outputs. The outputted unedited value shows it just stops at first 8 digits.

I'm not sure if it's the format specifiers (admittedly, idk what the correct specifier would be), but this is something I haven't really seen before. Any help would be appreciated, thank you.

Each hex digit stores up to 4 bits of information; 16 hex digits therefore store up to 64 digits of information, so if you should use unsigned long long.

... or you could just use a string.