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.
['3245', 'A', '3647', '9619', '2125', '5397', 'p', 's', '59', 'W', 'L', 'P', 'Y', '4609', '5757', 'e', '5333', '7361', 'i']