#include <bits/stdc++.h>
using namespace std;
const int N = 555;
inline int cal(int n, int m, int x, int y) { return (n - x + 1) * (m - y + 1); }
int main() {
  int n, m, s;
  while (~scanf("%d%d%d", &n, &m, &s)) {
    long long ans = 0;
    for (int h = 1; h <= n; h += 2)
      for (int w = 1; w <= m; w += 2)
        if (h * w >= s && 0 == (h * w - s) % 4) {
          int a = (h * w - s) / 4;
          int x = (h - 1) / 2, y = (w - 1) / 2;
          if (a == 0) {
            ans += 1LL * cal(n, m, h, w) * ((x + 1) * (y + 1) * 2 - 1);
            continue;
          }
          for (int i = 1; i * i <= a; i++)
            if (a % i == 0) {
              if (i * i == a) {
                if (i <= x && i <= y) ans += 2 * cal(n, m, h, w);
              } else {
                if (i <= x && a / i <= y) ans += 2 * cal(n, m, h, w);
                if (i <= y && a / i <= x) ans += 2 * cal(n, m, h, w);
              }
            }
        }
    cout << ans << endl;
  }
}
