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.
['V', '9051', 'S', 'c', 'i', '6951', 'R', '9063', '4265', '3255', '5509', 'O', '71', '3835', '1403', 'f', 'h', '5349', '8635', 'C']