import java.util.*; 

class Main{
public static void main(String[] args){
	Scanner sc=new Scanner(System.in);
        int x=sc.nextInt();
  		int t=0;
  if(x==2){
 	 System.out.println(x);
  }else{
  
   for(int x1=x;x1>0;x1++){
     for(int c=2;c<x1;c++){
         if(x1%c==0){
           t=0;
           break;
          }else{
           t++;
         }
    	 }
     if(t>0){
        System.out.println(x1);
           return;
     } 
   }

  }
    }
}
/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