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.
['p', '9605', 'W', 'J', '7643', 'C', 'P', 'm', 'F', 'R', '8407', 'q', 'Z', 'j', 'h', 'O', '2009', '7487', 'M', '9941']