#include <bits/stdc++.h>
int main() {
  int a = 0, b = 0, c = 0, n = 0, r = 1, e = 0;
  scanf("%d%d%d", &a, &b, &c);
  while (a <= b) {
    a = (a + n);
    e = c % a;
    n++;
    if (e == 0) r++;
  }
  printf("%d\n", r);
  return 0;
}
