#include <algorithm>
#include <cstdio>
#include <cstring>
#include <iostream>
#include <map>
#include <queue>
#include <set>
#include <sstream>
#include <string>
#include <vector>
#include <cmath>
using namespace std;

bool isprime(int n) {
    for (int i = 2; i * i <= n; i++) {
        if (n % i == 0) return false;
    }
    return true;
}

int solve(int n) {
    for (int i = n - 100; i <= n + 100; i++) {
        if (!isprime(i)) return i;
    }
}

int main() {
    int n;
    cin >> n;

    cout << solve(n) << endl;
}