As a general officer I once worked for used to say, if you need more decimal places, convert from English to Metric and back. He was being sarcastic, of course.
Heh; that’s more numbers than I need to deal with. I can’t even imagine those kind of mach speeds.
I once did 200mph (300ft/sec) laps testing BFG tires at Daytona in an mid-80s IMSA GTP Porsche 956, and that was plenty fast enough for me.