#include <iostream>
#include <vector>
#include <string>
#include <algorithm>
#include <iomanip>
using namespace std;
using ll = long long;


int main() {
    int N;
    cin >> N;
    for(int i=N-100; i<=N+100; ++i) {
        for(int j=2; j<i; ++j) {
            if(i % j == 0) {
                cout << i << endl;
                return 0;
            }
        }
    }
}