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.
['x', '413', '6953', '9953', 'j', 'B', 'Q', '7065', 'B', '6409', 'G', 'C', 's', 'i', '1593', 'O', 'h', '9631']