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#include <iostream>
#include <cmath>
#include <vector>

using ull = unsigned long long;

ull sito(ull f) {
	ull k = 1;
	std::vector<ull> prime;
	bool isP;
	ull fx = std::sqrt(f);

	for (ull i = 2; i <= fx; i++) {

		if (f % i == 0) {
			isP = true;

			for (int j = 0; j != prime.size(); j++) {

				if (i % prime[j] == 0) {
					isP = false;
					break;
				}

			}

			if (isP) {
				prime.push_back(i);
				k = i;
			}

		}

	}

	return k;
}

int main() {
	std::ios::sync_with_stdio(false);
	std::cin.tie();
	int n;
	ull f = 0, a, k;

	std::cin >> n;

	for (int i = 0; i < n; i++) {
		std::cin >> a;
		f += a;
	}

	k = sito(f);

	std::cout << k;
	return 0;
}