import java.util.*;
 
public class Main{
  public static void main(String[] args){
    Scanner sc = new Scanner(System.in);
    String S = sc.next();
    int N = S.length();
    String case1 = S.substring(0, N/2);
    String case2 = S.substring((N+3)/2-1, N);
    if(case1.equals(case2)){
      System.out.println("Yes");
    }else{
      System.out.println("No");
    }
  }
}
  
/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