#include <bits/stdc++.h>
using namespace std;
long long n, m, s;
long long ans = 0;
long long f(long long x, long long y) { return (n - x + 1) * (m - y + 1); }
int main() {
  scanf("%lld%lld%lld", &n, &m, &s);
  for (register long long i = 1; i <= n; i += 2)
    for (register long long j = 1; j <= m; j += 2) {
      long long s1 = i * j;
      if (s1 == s)
        ans += (((i - 1) / 2 + 1) * ((j - 1) / 2 + 1) * 2 - 1) * f(i, j);
      else if (s1 < s) {
        long long s2 = s - s1;
        if (s2 % 2) continue;
        for (register long long k = 1; k < j; k += 2)
          if (s2 % k == 0 && i + s2 / k <= n) {
            ans += 2 * f(i + s2 / k, j);
          }
      }
    }
  printf("%lld", ans);
  return 0;
}
