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.
['E', 'D', '9817', 'I', 'c', '489', 'M', '1025', 'a', 'V', 'p', 'i', '7613', '1535', 'Y', 'J', '9413', 'O', '1093']