#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, s;
  cin >> n >> m >> s;
  long long res = 0;
  for (int c = 0; c < (int)((n + 1) / 2); ++c)
    for (int b = 0; b < (int)((m + 1) / 2); ++b) {
      int h = 2 * c + 1;
      int w = 2 * b + 1;
      long long q = (n - h + 1) * (m - w + 1);
      int e = w * h - s;
      if (e == 0) {
        res += q * ((c + 1) * (b + 1) * 2 - 1);
      } else if (e > 0 && e % 4 == 0) {
        e /= 4;
        for (int i = 1; i <= b && i * i <= e; ++i) {
          if (e % i) continue;
          int j = e / i;
          if (j <= c) res += 2 * q;
          if (i <= c && j <= b && i != j) res += 2 * q;
        }
      }
    }
  cout << res << endl;
}
