import java.util.Scanner;

/**
 * String Palindrome
 * 
 * https://atcoder.jp/contests/abc159/tasks/abc159_b
 */
public class Main {

    static Scanner sc = new Scanner(System.in);

    public static void main(String[] args) throws Exception {
        String S = sc.next();
        int N = S.length();

        for (int i = 1; i <= (N - 1) / 2; i++) {
            if (S.charAt(i - 1) != S.charAt(N - i)) {
                System.out.println("No");
                return;
            }

            if (S.charAt(i - 1) != S.charAt((N - 1) / 2 - i)) {
                System.out.println("No");
                return;
            }
        }

        System.out.println("Yes");
    }

}

/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