Prop the little beauty on it's back and a penetrating oil dribbled around the beaters where the enter the sockets left a few days may do the work. Wiggle'm back and forth and try some brute force. They've been put away wet and rusted..
One those beaters you kind of grasp those little washers with your thumb and forefinger up by the sockets and give them a little flip, the beaters should just pop out if they're not jammed. That's how they're supposed to work anyways.
You can take the front cover off and pry the beaters out. As mixerfinder pointed out, they were probably put away wet. I had this happen to a couple of mine and I did manage to get them out...eventually!