Blocks are every 2.5 minutes. That's 576 X 2.5 minute blocks in a day. That's 4,032 blocks in a week. So there are  4,032 blocks in a week  X 52 weeks in  a year  = 209,664 blocks in a year. Block reward is 25 coins initially so at 209,664 blocks in a year x 25 coins block rewards = 5,241,600 coins in the first year (roughly).

It will take 35 days for miners to catch-up to the premine.