Any router is compatible, though you should check to make sure the WAN port is capable of the Internet speeds you're paying for. Some cheap routers use a 100 Mbps ethernet port for the WAN port, limiting you to 100 Mbps to your ISP.
Comcast uses DOCSIS-compatible modems. Which revision depends on how much speed you're paying for (or plan to upgrade to in the future). DOCSIS 2.0 is good for up to about 40 Mbps down, 30 Mbps up. DOCSIS 3.0 varies by individual modem in how much speed they support. The number you want to look for is how many streams they support. Earlier 8x4 DOCSIS 3.0 modems could only get you about 300 Mbps down, 150 Mbps up max (each stream is about 40 Mbps, so 8*40 = 320 Mbps down, 4*40 = 160 Mbps up). Higher end models will do 16x8 or 20x8. etc.
The Motorola/Arris SURFboard modems are extremely popular and very good in my experience.
If you want to stick to Comcast's approved device list, they have a webpage for it.
https://www.xfinity.com/support/articles/list-of-approved-cable-modems
As above, I recommend a separate modem and router, for less hassles when upgrading. And pretty much every cable company uses DOCSIS-compatible modems, so you should be able to continue using it even if you move to an area with a different cable ISP.