PCGS has graded over 8,300 coins with the PCGS number 624779 in PR 70 condition. Each coin has an individual certification number. I believe that is what you are seeing. The Cert # of the eBay listing comes up as one of the 8,300+ when checked on the PCGS web site.
Collecting history one coin or medal at a time! (c) commems. All rights reserved.