#include <bits/stdc++.h>
using namespace std;
#pragma comment(linker, "/STACK:1024000000,1024000000")
int main() {
  ios_base::sync_with_stdio(0);
  cin.tie(0);
  srand(__rdtsc());
  long long n, m, S;
  cin >> n >> m >> S;
  long long ans = 0;
  long long add;
  for (long long a = 1; a <= n; a += 2)
    for (long long b = 1; b <= m; b += 2) {
      add = 0;
      if (a * b < S) continue;
      if (a * b == S)
        add = 2 * (a / 2 + 1) * (b / 2 + 1) - 1;
      else {
        long long S1, d;
        S1 = a * b - S;
        if (S1 % 4) continue;
        S1 /= 4;
        long long b2 = b / 2;
        for (long long c = a / 2; c > 0; c--)
          if (S1 % c == 0 && S1 / c <= b2) add += 2;
      }
      ans += add * (n - a + 1) * (m - b + 1);
    }
  cout << ans << endl;
  return 0;
}
