I guess AA doesn't have a sense of humor by this definition:
1776 is DFW-MCO (nothing of revolutionary significance happened in either place)
1492 is SLC-ORD-ATL (ditto for ol' Chris)
911 is LAX-MIA-SCL (maybe the two US cities have a high number of 911 calls, but I don't think AA would try to do anything with that)
711, 777 don't exist (neither do 13, 666)
500 is ORD-DCA (no magic here)
My Nov. 1 print timetable shows 2711 LAS-LAX, but the Web doesn't have it. I suspect the number was random.