Yes, but--the magnificent 19 were actually 20, but one got arrested before he could act.
The cells are alway 5 men, no? (Except that now, there are also women.)
They said allah willed it that way. ;-)
OPINION: Cells these day seem to run about 3-5 people, but suiciders come in 1 lone individual or a 2 person team.
They no doubt see it as a divine symbol that the number ended up being 19, on 11-9 (by the way they read dates), so they will put even more significance on that number
Consider also: the 1 and 9 trains on the IRT, running the West Side, one of the most heavily traveled routes.
I don't believe there was a 20th hijacker planned for 9/11. Moussaoui has claimed he was part of a seperate plot.