#include <bits/stdc++.h>
int i, j, k, l, I, J;
int n, m, s;
long long ans, c, d;
int main() {
  scanf("%d%d%d", &n, &m, &s);
  for (i = 0; I = i * 2 + 1, I <= n; i++) {
    for (j = 0; J = j * 2 + 1, J <= m; j++) {
      if (I * J == s) {
        c = (n - I + 1) * (m - J + 1);
        d = ((i + 1) * (j + 1) - 1) * 2 + 1;
        ans += c * d;
      } else if (I * J > s) {
        for (k = 1; k <= i; k++) {
          l = (I * J - s) / k >> 2;
          if (l <= j && s == I * J - 4 * (k * l)) {
            c = (n - I + 1) * (m - J + 1);
            d = 2;
            ans += c * d;
          }
        }
      }
    }
  }
  printf("%I64d\n", ans);
  return 0;
}
