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#include <bits/stdc++.h>
using namespace std;

#define ll long long
#define st first
#define nd second
#define ld long double

bool sprawdz (ll k, vector<ll> &a, int n) {
    vector<ll> s (n+k, 0);
    ll x = 0;
    for (int i = 0; i < n; i++) {
        x += s[i];
        if (x < a[i]) {
            s[i+k] -= a[i]-x;
            x = a[i];
        }
        else if (x > a[i]) {
            return 0;
        }
    }
    return x+s[n]==0;
}

void solve() {
    int n;
    cin >> n;
    vector<ll> a (n);
    ll s = 0;
    for (ll &i : a) {
        cin >> i;
        s += i;
    }
    set<ll> d;
    for (ll i = 1; i*i <= s; i++) {
        if (s%i==0) {
            if (i <= n) {
                d.insert(i);
            }
            if (s/i <= n) {
                d.insert(s/i);
            }
        }
    }
    vector<ll> ok, nok;
    while (!d.empty()) {
        int l = d.size();
        int r = rand()%l;
        auto pt = d.begin();
        for (int i = 0; i < r; i++, pt++);
        ll x = *pt;
        d.erase(pt);
        bool q = 0;
        for (ll i : ok) {
            if (i%x == 0) {
                q = 1;
                ok.push_back(x);
                break;
            }
        }
        for (ll i : nok) {
            if (x%i == 0) {
                q = 1;
                nok.push_back(x);
                break;
            }
        }
        if (q) continue;
        q = sprawdz(x, a, n);
        if (q) ok.push_back(x);
        else nok.push_back(x);
    }
    sort(ok.begin(), ok.end());
    cout << ok[ok.size()-1] << '\n';
}

int main() {
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    srand(67);
    int t=1;
    //cin >> t;
    for (int i = 0; i < t; i++) {
        solve();
    }
}