I only have fourteen, including four two-week old chicks. All of them, including the chicklets come when I call! The adults taught them that within days. They’re being raised by a broody, but they already will sit on my lap.I've only had a couple of chickens who were so tame as to sit in my lap. They only became that way when they were teenagers (5-8 weeks old) and I only had 6 chickens. I would sit on the ground or in a chair in their area for quite a while every night. I sometimes had treats, but not always. Mealworms are their favorite. I would let them fly up on my leg, shoulder, or even my head sometimes. I feel like it was just a matter of spending enough time with them that they feel you are part of the flock.
Now that they are much older (4 yrs old) and I have a rather large flock (50+ chickens), they don't come sit in my lap anymore or really even allow me to pet them unless I take them off the roost, but they will follow me around or even come when I call. All my chickens are constantly underfoot when its feeding time. They know I bring treats frequently so they are always trying to see what I've got in my hands, bowl, or bucket.