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.
['4433', 'r', 'c', 'y', 'a', 'm', '2919', 'm', '6797', 'o', 'u', 'E', '6029', '8377', 'e', 'a', 'n', 'I', 'S', '8895']