#include <bits/stdc++.h>
using namespace std;
const int MAX = 100;
int N, M, S;
long long count_all(int x1, int y1, int x2, int y2) {
  int x = max(x1, x2);
  int y = max(y1, y2);
  return (N - 2 * x) * (M - 2 * y);
}
int solve(int x1, int y1, int x2) {
  int y2 = -1;
  int area = (2 * x1 + 1) * (2 * y1 + 1);
  if (S > area) {
    int rest = S - area;
    if (rest % 2 == 0) {
      rest /= 2;
      if (rest % (2 * x2 + 1) == 0) y2 = rest / (2 * x2 + 1) + y1;
      if (y2 >= (M + 1) / 2) y2 = -1;
    }
  }
  return y2;
}
int main() {
  cin >> N >> M >> S;
  long long ret = 0, one = 0;
  if (S & 1) {
    for (int i = 0; 2 * i + 1 <= N; ++i)
      for (int j = 0; 2 * j + 1 <= M; ++j) {
        if ((2 * i + 1) * (2 * j + 1) == S) {
          ret += (i + 1) * (j + 1) * 1LL * count_all(i, j, i, j);
          one += count_all(i, j, i, j);
        }
        for (int k = 0; k < i; ++k) {
          int ans = solve(i, j, k);
          if (ans >= 0) ret += count_all(i, j, k, ans);
        }
      }
  }
  printf("%I64d\n", ret * 2 - one);
  return 0;
}
