#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, s;
  cin >> n >> m >> s;
  long long Ans = 0;
  for (int a = 1; a <= n; a += 2) {
    for (int b = 1; b <= m; b += 2) {
      for (int d = 1; d <= m; d += 2) {
        int bd = min(b, d);
        if ((s - a * b + a * bd) % d == 0) {
          int c = (s - a * b + a * bd) / d;
          if (c % 2 && a <= c && c <= n) {
            Ans += (long long)(n - max(a, c) + 1) * (m - max(b, d) + 1);
          }
        }
      }
    }
  }
  for (int c = 1; c <= n; c += 2) {
    for (int b = 1; b <= m; b += 2) {
      for (int d = 1; d <= m; d += 2) {
        int bd = min(b, d);
        if ((s - c * d + c * bd) % b == 0) {
          int a = (s - c * d + c * bd) / b;
          if (a % 2 && c < a && a <= n) {
            Ans += (long long)(n - max(a, c) + 1) * (m - max(b, d) + 1);
          }
        }
      }
    }
  }
  cout << Ans << endl;
}
