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// clang-format off
#include<bits/stdc++.h>
using namespace std;
using LL=long long;
#define FOR(i,l,r) for(auto i=(l);i<=(r);++i)
#define REP(i,n) FOR(i,0,(n)-1)
#define ssize(x) int(x.size())
auto operator<<(ostream&o,auto p)->decltype(p.first,o){return o<<"("<<p.first<<", "<<p.second<<")";}
auto operator<<(ostream&o,auto x)->decltype(x.end(),o){o<<"{";int i=0;for(auto e:x)o<<(", ")+2*!i++<<e;return o<<"}";}
#ifdef DEBUG
#define debug(x...) cerr<<"["#x"]: ",[](auto...$){((cerr<<$<<"; "),...);}(x),cerr<<'\n'
#else
#define debug(...) {}
#endif
// clang-format on

vector<int> primes;
void
prepro_primes()
{
    const int MAX_N      = 316227;
    const int MAX_N_SQRT = sqrt(MAX_N);
    vector<bool> sieve(MAX_N + 1);
    FOR (p, 2, MAX_N) {
        if (sieve[p]) continue;
        primes.emplace_back(p);
        if (p > MAX_N_SQRT) continue;
        for (int i = p * p; i <= MAX_N; i += p) sieve[i] = true;
    }
}

bool check(const vector<int> &diffs, int k);

int
main()
{
    cin.tie(0)->sync_with_stdio(0);
    int N;
    cin >> N;
    vector<int> seq(N);
    for (auto &x : seq) cin >> x;

    // Generate sequence of differences
    vector<int> diffs(N + 1);
    diffs[0] = seq[0], diffs[N] = -seq[N - 1];
    FOR (i, 1, N - 1) diffs[i] = seq[i] - seq[i - 1];
    debug(diffs);

    // K works => every divisor of K works
    // prime p does not work => p !| K

    // K has to be a divisor of sum, so I just check primes that divide sum
    LL sum = accumulate(seq.begin(), seq.end(), (LL)0);

    // sum may be a huge prime and K == sum
    if (sum <= N and check(diffs, sum)) {
        cout << sum << "\n";
        return 0;
    }

    // List primes of sum
    // need to only check primes K <= sqrt(sum) <= 316227
    prepro_primes();
    vector<int> sum_primes;
    for (const auto &prime : primes) {
        if (sum % prime == 0) sum_primes.emplace_back(prime);
    }
    debug(sum_primes);

    // Throw out some primes
    // assert(ssize(sum_primes) <= 11);
    LL Kdivides = sum;
    for (const auto &prime : sum_primes) {
        if (prime <= N and check(diffs, prime)) continue;
        while (Kdivides % prime == 0) Kdivides /= prime;  // get rid of prime
    }

    // Check K
    for (int k = N; k > 0; --k) {
        if (Kdivides % k != 0) continue;
        if (!check(diffs, k)) continue;
        cout << k << "\n";
        return 0;
    }

    cout << "1\n";
    return 0;
}

bool
check(const vector<int> &orig_diffs, int k)
{
    auto diffs = orig_diffs;
    int N      = ssize(diffs) - 1;
    FOR (i, 0, N - k) {
        if (diffs[i] < 0) return false;
        diffs[i + k] += diffs[i];
    }
    FOR (i, N - k + 1, N)
        if (diffs[i] != 0) return false;
    return true;
}