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