Originally Posted by Shmevin

Elo is not necessarily easier or more difficult to gain, rather it's harder to maintain a high elo and it's next to impossible to farm rank without getting caught. You really have to be skilled to keep a good rank. The more elo you have, the better you have to perform to maintain that number, let alone gain more.
I'm not sure exactly how many games you need to play in order to acquire 1660 elo, that really depends on your win/loss ratio as well as the elo of the players you face while matchmaking.