#include <bits/stdc++.h>
using namespace std;
int n, m, s;
long long ans = 0;
int main() {
  scanf("%d%d%d", &n, &m, &s);
  for (int xl = 1; xl <= n; xl += 2) {
    int ly = (s + xl - 1) / xl;
    if (ly % 2 == 0) ++ly;
    for (int yl = ly; yl <= m; yl += 2) {
      long long num = (n - xl + 1) * (m - yl + 1);
      int sz = xl * yl - s;
      if (sz == 0)
        ans += num * ((xl / 2 + 1) * (yl / 2 + 1) * 2 - 1);
      else if (sz % 4 == 0) {
        for (int xp = 2; xp < xl; xp += 2)
          if (sz % xp == 0) {
            int t = sz / xp;
            if (t < yl && t % 2 == 0) ans += num * 2;
          }
      }
    }
  }
  cout << ans << endl;
  return 0;
}
