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.
['y', 'i', '6451', 'x', 'd', '7865', 'q', '9649', 'v', 'E', '7337', 'M', '4105', '7191', 'X', 'Q', '7745', '325']