https://www.speedguide.net/port.php?port=912 is an example find. None of those on the list appear to be of much concern. Why would I write that? It's pretty simple. ALL inbound UNSOLICITED CONNECTION REQUESTS FAIL because a stock configured router doesn't route them. It just drops the packets and that's the end.

I've found so many run port scans and not know this basic truth. Those that sell firewall apps won't tell you this.