import java.util.*;
public class Main
{
    public static void main(String args[])
    {
        Scanner sc=new Scanner(System.in);
        boolean arr[]=new boolean[100004];
        for(int i=2;i*i<100004;i++)
        {
            for(int j=i*i;j<100004;j+=i)
            arr[j]=true;
        }
        int n=sc.nextInt();
        for(int i=n;i<arr.length;i++)
        {
            if(!arr[i])
            {
                System.out.println(i);
                break;
            }
        }
    }
}
/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