import java.util.Scanner;

public class Main {
    public  static boolean check(int x) {
        for(int i=2;i*i<=x;i++) {
            if(x%i==0) return false;
        }
        return true;
    }
    public static void main(String[] args) {
        Scanner in=new Scanner(System.in);
        int x=in.nextInt();
        while(true) {
            if(check(x)) {
                System.out.println(x);
                break;
            }
            x++;
        }
    }
}
/tmp/hf-datasets-cache/medium/datasets/42704881117311-config-parquet-and-info-qiankunmu-Project_CodeNet-896c9d36/hub/datasets--qiankunmu--Project_CodeNet_Python800_and_Java250/snapshots/c899fde44a77ba1cc14973ed3de064e4ff3aadc7/Project_CodeNet_Java250.tar.gz