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.
['3085', 'p', 'T', '5241', 'a', '151', 'Q', '6287', '1229', 'Z', '9533', 'Y', '6487', '5343', '3407', '8527', 'o', '449', 'p']