#include <bits/stdc++.h>
using namespace std;
int main() {
  int n, m, s;
  while (scanf("%d%d%d", &n, &m, &s) != EOF) {
    int lx, ly, yl, i, j, k, sz;
    long long num, ans = 0;
    for (lx = 1; lx <= n; lx += 2) {
      ly = (s + lx - 1) / lx;
      if (!(ly & 1)) ly++;
      for (; ly <= m; ly += 2) {
        sz = lx * ly - s;
        num = (n - lx + 1) * (m - ly + 1);
        if (sz == 0) {
          ans += num * ((lx / 2 + 1) * (ly / 2 + 1) * 2 - 1);
        } else if (sz % 4 == 0) {
          for (i = 2; i < lx; i += 2) {
            if (sz % i) continue;
            j = sz / i;
            if (j >= ly || (j & 1)) continue;
            ans += 2 * num;
          }
        }
      }
    }
    printf("%I64d\n", ans);
  }
  return 0;
}
