#include <bits/stdc++.h>
using namespace std;
int n, m, s;
int main() {
  long long ans = 0;
  scanf("%d%d%d", &n, &m, &s);
  for (int i = 1; i <= n; i += 2)
    for (int j = 1; j <= m; j += 2) {
      if (i * j == s)
        ans += 1ll * (n - i + 1) * (m - j + 1) *
               ((i / 2 + 1) * (j / 2 + 1) * 2 - 1);
      if (i * j > s) {
        if ((i * j - s) % 4) continue;
        int t = (i * j - s) / 4;
        for (int k = 1; k * 2 + 1 <= i; ++k) {
          if (t % k) continue;
          if (t / k * 2 + 1 > j) continue;
          ans += 2ll * (n - i + 1) * (m - j + 1);
        }
      }
    }
  printf("%I64d\n", ans);
  return 0;
}
