Chalo explained it perfect. But if there is a rpm limiter built into the controller, it will then turn off power at that 22 mph speed. So freewheeling or not, whatever the no load of motor may be, the system is at least lowering the power at 22 mph.
The best way to really find out is to put a watt meter between your battery and your motor. When its showing about 5w its not running the motor, its just keeping the display and controller lit up. The wattmeter will show you when the motor is at no load, or when a limiter kicks on.
Watt meters are really fun, in addition to what the motor is doing, they can show you what you contribute. Example, ride 15 mph pedaling, then stop pedaling. The difference in watts is approximately what your pedaling contributed. The number is not really accurate, (Because the motor and controller wastes some watts) but it does give a number you can compare to other speeds, or levels of effort. Repeat the experiment with varying effort. You can see motor only takes 200 w to go 15 mph or whatever, then turn off the motor and see what keeping up that speed feels like. With experience, you can learn what that feels like in pedal pressure on your foot. Now you can judge your personal output on any bike, at any time. For me, I needed to keep my effort below 75w, because of an illness I have. So at any speed, I tried to aim for that much effort, judged by the pedal feel, my rate of breathing, etc. Under 75w, no limit to the distance, over it, I would get sick quickly.