function Main(input) {
	var str = input;
	var ans = "";
	str = str.split("\n")[0];
	str = str.split(" ")[0];
	var arr = str.split('');
	var n = arr.length;
	var c = (n+3)/2-1;
	var f = arr.splice(c, n-c);
	var b = arr.splice(0,c-1);
	
	f = f.join("");
	b = b.join("");


	if(b === f){
		ans = "Yes"
	}else{
	ans = "No"
	}
	console.log(ans);
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));