Stepper motors - stride angle?
The notation 5.625°/64 indicates that the motor has a step angle of 5.625°, and the output shaft is driven via a 64:1 gear ratio.  If you look at the picture of the motor, you can see that that output shaft is offset from the center of the unit, also indicating a geared output shaft.

So, following through, the motor has 360/5.625 = 64 steps/rev, but the output shaft has 64 steps/rev * 64 gear ratio = 4096 steps/rev, or 0.088°/step

That should be plenty of precision for you!