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#include <bits/stdc++.h>

using namespace std;

#define ll long long

#define rng(i,a,b) for(int i=int(a);i<int(b);i++)
#define rep(i,b) rng(i,0,b)

typedef vector<int> vi;
typedef vector<vi> vvi;
typedef vector<vvi> vvvi;

typedef vector<ll> vl;
typedef vector<vl> vvl;
typedef vector<vvl> vvvl;

typedef pair<int,int> ii;

template<class t> using vc=vector<t>;
template<class t> using vvc=vc<vc<t>>;

const int MOD = 998244353;

ll read(){
    ll i;
    cin>>i;
    return i;
}

vi readvi(int n,int off=0,int shift=0){
    vi v(n+shift);
    rep(i,shift)v[i]=0;
    rep(i,n)v[i+shift]=read()+off;
    return v;
}

void YesNo(bool condition, bool do_exit=true) {
    if (condition)
        cout << "Yes" << endl;
    else
        cout << "No" << endl;
    if (do_exit)
        exit(0);
}

bool test(int n, vi & a, int k) {
    vi finished(n+1);
    rep (i,n) {
        int num = (i ? a[i-1] : 0) - finished[i]; // tyle przechodzi z lewej
        // jest a[i] - num lewych końców w i.
        if (a[i] - num < 0)
            return false;

        if (a[i] - num > 0) {
            if (i + k <= n)
                finished[i+k] = a[i] - num;
            else
                return false;
        }
    }
    return true;
}

int main(void ) {
    ios::sync_with_stdio(false);
    cin.tie(NULL);

    int n;
    cin >> n;
    vi a = readvi(n);

    ll sum = 0;
    rep(i,n)
        sum += a[i];

    vector prime(n+1,true);

    int res = 1;
    rng(i,2,n+1)
        if (prime[i]) {
            if (sum % i == 0 and test(n,a,i))
                res = i;
            else {
                int j = i;
                while (j+i <= n) {
                    j += i;
                    prime[j] = false;
                }
            }

        }

    cout << res << endl;

    return 0;
}