#include <bits/stdc++.h>
using namespace std;
const double eps = 1e-10;
long long n, m, s;
int main() {
  cin >> n >> m >> s;
  long long ans = 0;
  for (long long a = 1; a <= n && a <= s; a += 2LL)
    for (long long b = 1; b <= m && a * b <= s; b += 2LL) {
      if (a * b == s) {
        ans += (n - a + 1LL) * (m - b + 1LL) *
               (((a + 1LL) / 2LL) * ((b + 1LL) / 2LL) * 2 - 1LL);
        continue;
      }
      long long ss = s - a * b;
      for (long long c = 1; c <= n; c += 2LL) {
        if (c < a) {
          if (ss % c != 0) continue;
          long long d = ss / c + b;
          if (d > m || d % 2 != 1) continue;
          ans += (n - a + 1LL) * (m - d + 1LL);
        } else if (c > a) {
          if (ss % (c - a) != 0) continue;
          long long d = ss / (c - a);
          if (d >= b || d > m || d % 2 != 1) continue;
          ans += (n - c + 1LL) * (m - b + 1LL);
        }
      }
    }
  cout << ans << endl;
  return 0;
}
