In this task, you are given an input list A. You need to find all the elements of the list that are numbers and calculate their sum.
['7883', 's', 'b', 'f', 'i', '1947', '5773', '2113', 'X', 'h', '4815', '411', 'J', 'E', '235', '8417', '9955', 'Z']