#include <iostream>

using namespace std;

int del(int n) {
	int cnt = 0;
	for (int i = 2; i <= n; ++i) {
		if (n % i == 0) cnt++;
	}
	return cnt;
}

int f(int n, int i = 0) {
	int cnt = del(n - i);
	if (del(++n) != cnt) {
		f(++n, ++i);
	}
	else {
		return n;
	}
}

int main() {
	int n;
	cin >> n;
	cout << f(n) << endl;
	return 0;
}