import java.util.*;
public class Main{
	public static void main(String [] args){
    	Scanner scan = new Scanner(System.in);
      	int x = scan.nextInt();
 		int [] arr = new int[(int)1e5+10];
      	int size = arr.length;
      arr[1]=1;
      arr[2]=1;
      arr[3]=1;
      	for(int i=4;i<size;i++){
          boolean isPrime=true;
        	for(int j=2;j<=Math.sqrt(i);j++){
            	if(i%j==0){
                  isPrime=false;
                  break;
                }
            }
          if(isPrime){
          arr[i]=1;
          }
        }
      	for(int i = x;i<size;i++){
        	if(arr[i]==1){
            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