#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, s;
  cin >> n >> m >> s;
  long long ans = 0;
  for (int i = 1; i <= n; i += 2) {
    for (int j = 1; j <= m; j += 2) {
      if (i * j == s) {
        long long temp = (i / 2 + 1) * (j / 2 + 1) * 2ll - 1;
        ans += temp * (n - i + 1) * (m - j + 1);
      } else if (i * j > s) {
        if ((i * j - s) % 4 != 0) continue;
        long long r = (i * j - s) / 4;
        for (int ii = 1; ii * 2 + 1 <= i; ii++) {
          if (r % ii != 0) continue;
          int jj = r / ii;
          if (jj * 2 + 1 > j) continue;
          ans += 2ll * (n - i + 1) * (m - j + 1);
        }
      }
    }
  }
  cout << ans << endl;
}
