#include <bits/stdc++.h>
using namespace std;
int n, m, s;
long long ans;
int main() {
  cin >> n >> m >> s;
  for (int i = 1; i <= n; i += 2) {
    for (int j = 1; j <= m; j += 2) {
      if (i * j == s) {
        ans += (long long)(2 * (i / 2 + 1) * (j / 2 + 1) - 1) * (n - i + 1) *
               (m - j + 1);
      }
      if (i * j > s && (i * j - s) % 4 == 0) {
        int sqr = (i * j - s) / 4;
        for (int k = 1; k < i / 2 + 1; k++) {
          if (sqr % k == 0 && 2 * k < i && 2 * sqr / k < j) {
            ans += 2 * (n - i + 1) * (m - j + 1);
          }
        }
      }
    }
  }
  cout << ans << endl;
  return 0;
}
