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#include <bits/stdc++.h>
#include <bits/extc++.h>

using namespace std;
using namespace __gnu_pbds;

#define DEBUG
#ifdef DEBUG
template<typename T1,typename T2>auto& operator<<(ostream&o,pair<T1,T2>a){return o<<"("<<a.first<<", "<<a.second<<")";}
template<typename T,size_t...I>void pt(ostream&o,T t,index_sequence<I...>){o<<"(";(...,(o<<(I?", ":"")<< get<I>(t)));o<<")";}
template<typename...A>auto& operator<<(ostream&o,tuple<A...>t){pt(o,t,index_sequence_for<A...>{});return o;}
template<typename T,typename O>auto& operator<<(O&o,T a){o<<"{";for(auto b:a)o<<b<<", ";return o<<"}";}
#define db(x...) cerr << "\033[92m" << "[" #x "]: ", [](auto... args) { ((cerr << args << ", "),...) << "\033[0m" << "\n"; }(x)
#else
#define db(...)
#endif

#define sz(x) ((int)(x).size()) 
#define all(x) (x).begin(), (x).end()
#define F first
#define S second

template<class T>
using iset = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
using ll = long long;
using ld = long double;
using pll = pair<ll,ll>;
using vi = vector<int>;

mt19937 mrand(random_device{}());
ll rnd(ll l, ll r) { return l + mrand() % (r - l + 1);}

ll n;
vector<ll> v;

bool check(ll k) {
    vector<ll> s = v;
    vector<ll> upd(n);
    ll cur = 0;
    for(ll i = 0 ; i < n ; ++i) {
        cur -= upd[i];
        s[i] -= cur;
        if(s[i] < 0) return false;
        if(i+k <= n) {
            cur += s[i];
            if(i+k < n) upd[i+k] += s[i];
            s[i] = 0;
        }
        if(s[i] != 0) {
            return false;
        }
    }
    return true;
} 

int main() {
    cin.tie(0)->sync_with_stdio(0); cin.exceptions(cin.failbit);

    cin >> n;
    v = vector<ll>(n);
    for(ll i = 0 ; i < n ; ++i) cin >> v[i];

    vector<ll> is_prime(n+7, true);
    is_prime[0] = is_prime[1] = false;
    for(ll i = 2 ; i < n+7 ; ++i) {
        if(!is_prime[i]) continue;
        for(ll j = 2*i ; j < n+7 ; j += i) {
            is_prime[j] = false;
        }
    }

    ll ans = 1;
    ll sum = std::accumulate(all(v), 0ll);
    for(ll i = 2 ; i <= n ; ++i) {
        if(sum % i == 0 && check(i)) ans = max(ans, i);
    }
    cout << ans;

    return 0;
}