ProblemSet1 - Credit.c - Issues assigning the sum of the numbers on a variable

So I coded the first lines of the Luhn's Algorithm and tried to print the values of some of my variables to be sure they were doing exactly what I want it. For my surprise they weren't. And I were here thinking for hours trying to figure out what was wrong. The "printf" keeps returning a bunch of zeros as the values of the variables. Let me know what you guys think about it and thanks for all the answers, have a good night. :)

So this is what I coded so far:

#include <cs50.h>
#include <stdio.h>
#include <math.h>

long number;
int count;
int digits;
int sum_1;
int sum_2;

int main(void)
{
do
{
number = get_long("Number: "); //Ask the CC number.
}
while(number < 0); //If the user answer a negative value, ask again.

while(number != 0) //Count the number of digits.
{
number /= 10;
count++;
}
for (digits = 1; digits <= count; digits++)
{
int ten_counter = pow(10, digits);

if (digits % 2 == 0)
{
sum_1 += (number % ten_counter);
}
else
{
sum_2 += (number % ten_counter);
}
printf("%i",sum_1);
printf("%i",sum_2);
}

}