#include <bits/stdc++.h>
int main(void) {
  int i = 0;
  int a, b, c, temp;
  scanf("%d%d%d", &a, &b, &c);
  if (a > b) {
    temp = a;
    a = b;
    b = temp;
  }
  temp = a;
  while (temp != b) {
    if (c % temp == 0) i++;
    temp++;
  }
  printf("%d\n", i);
  return 0;
}
