Many airfoils start the stall at about 15° angle of attack. At that value, and accounting for inflowing air, a square prop does not stall at 3/4 diameter and outward, where the prop does most work, and at rpm that have tipspeeds below mach 0.7.
The prop circle inside 3/4 diameter however may stall, and produce the typical stalled sound, depending on rpm. All in all, I think the stall in props is much talked about, but not an everydays occurrence in most applications. Hotliners and speed flight yes.