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.
['z', '3887', 'E', 'T', 'Y', 'z', '2991', 'R', '6719', 'Q', '8569', '9853', 'Y', 'm', '2515', 'x', 'm', 'h']