The quote part is simply an incremental counter. First you have the topic ID, then you have the message ID. These are simply incremental counters in the database behind the site.
The message ID, you might notice, is quite large for this topic. That's because its ID doesn't care about which post it's on. It only cares about its position relative to the rest as it's in its own database table.
The date part is a bit more complicated, but it's still simple. It's merely what's known as a Unix timestamp, or Epoch time. The Epoch is defined as January 1st,1970 at exactly 0000 hours UTC. The Epoch timestamp is merely the number of seconds since that time, and has become the standard for timestamps (well, there are other formats, but Epoch time is the easiest).