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.
['6365', 'Z', '1605', 't', 'w', '4169', 'F', '3233', 'p', '9173', '9505', '4713', 'O', '4355', 'X', 'A', 'g', '4471', '9191']