If multiple network interfaces defines a router, then every cell phone is one, because every cell phone has a cellular and Wifi interface, and is a router in hotspot mode. Three interfaces if you count USB which can also be a network interface (hotspot works over USB in both Windows and Linux) and four if Bluetooth PAN is still a thing.

All routers ship with software.

(edit: and RAM!)

(edit: and NOT multiple video outputs!!)