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#include <cstdio>
#include <vector>

typedef long long LL;

using namespace std;

int n;
vector<int> a;

bool test(int k) {
  LL sum = 0;
  vector<int> t(k, 0);
  int j = k-1;
  for (int i=0; i<n; ++i) {
    if (++j >= k) j -= k;
    sum -= t[j];
    if (sum > a[i]) return false;
    t[j] = a[i]-sum;
    sum += t[j];
  }
  sum -= t[n%k];
  return sum == 0;
}

vector< pair<LL, int> > fact;
LL rec(int k, LL v) {
  if (v > n) return 0;

  if (k >= fact.size()) {
    return test(v) ? v : 0;
  }

  LL res = 0;
  for (int i=0; i<=fact[k].second; ++i) {
    LL tmp = rec(k+1, v);
    if (tmp == 0) break;
    res = max(res, tmp);
    v *= fact[k].first;
  }
  return res;
}

int main() {
  scanf("%d", &n);
  a.resize(n);
  LL sum = 0;
  for (int i=0; i<n; ++i) {
    scanf("%d", &a[i]);
    sum += a[i];
  }

  for (LL i = 2; i*i <= sum; ++i) {
    while (sum % i == 0) {
      if (fact.empty() || fact.back().first != i) {
        fact.emplace_back(i, 1);
      } else {
        fact.back().second++;
      }
      sum /= i;
    }
  }
  if (sum > 1) fact.emplace_back(sum, 1);
 
  printf("%lld", rec(0, 1));
  return 0;
}