#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
 
int main()
{
	string s,s1,s2,sr;
	cin>>s;
	ll n=s.size();
	sr=s;
	reverse(sr.begin(),sr.end());
  	if(sr==s)
  	{
  		s1=s.substr(0,n/2);
  		s2=s.substr(n/2+1,n/2);
  		if(s1==s2)cout<<"Yes\n";
  		else cout<<"No\n";
	  }
	  else cout<<"No\n";
}