#include <bits/stdc++.h>
using namespace std;
long long N, M, S;
void init() { cin >> N >> M >> S; }
void work() {
  long long a, b, i;
  long long ANS = 0;
  for (a = 1; a <= N; a += 2) {
    for (b = 1; b <= M; b += 2) {
      if (a * b == S) {
        ANS += (N - a + 1) * (M - b + 1) * ((a / 2 + 1) * (b / 2 + 1) * 2 - 1);
      } else {
        if (a * b > S) continue;
        long long tmp = S - a * b;
        if (tmp % 2 == 0) {
          for (i = 2; i + b <= M; i += 2) {
            if (tmp % i) continue;
            if (tmp / i >= a) continue;
            if (tmp / i % 2) ANS += (N - a + 1) * (M - b - i + 1) * 2;
          }
        }
      }
    }
  }
  cout << ANS << endl;
}
int main() {
  init();
  work();
  return 0;
}
