#include <bits/stdc++.h>
using namespace std;
vector<int> vi;
vector<long long> vll;
const int mod = 1000000007;
const double pi = acos(-1.0);
int pos[2000003];
int main() {
  long long x;
  long long c = 0, i, j;
  string s, ss;
  map<char, int> mp;
  cin >> s;
  for (i = 0, j = s.size() - 1; i<j, j> i; j--, i++) {
    if (s[i] != s[j]) c++;
  }
  if (c == 0 and s.size() % 2 == 0)
    cout << "NO" << endl;
  else if (c == 1 and s.size() % 2 == 0)
    cout << "YES" << endl;
  else if (c == 1 or c == 0 and s.size() % 2 != 0)
    cout << "YES" << endl;
  else
    cout << "NO" << endl;
  return 0;
}
