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.
['87', '9259', 'g', 'z', 'X', 'c', 'l', 'M', 'x', 'T', '2113', '7357', 'e', 'Z', '2467', 't', '7185', 'p', '1003', '4373']