depends how much room you have... if you can get far back enough i'm sure you could but it wouldn't be ideal. Heck i'd have a tough time getting 22 people to fit into the shot with my lens at 18mm
wouldn't be your best option. If you move back far enough fine...but you're going to have to move people together, stagger them...sit some down...you know.
Thats the first thing I noticed on my D200 and the 50... it was narrow!
At that moment, I was glad I had several options in the 10-50mm range for lens choices to help me out.
Indoors there is not usually enough room to get 22 people in a picture unless you are in a place like a school gym or something bigger than your average basement or livingroom.
Enough ambient light for a small aperature outdoors? Are you shooting at dusk? As long as you can shoot from 40 feet back or so it shouldn't be a problem with that lens (50/1.8).