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.
['3053', 'h', '7445', 'f', '2613', '7837', 'q', 'J', 'n', 't', 'Q', '2517', '2677', 'Z', 'V', '6665', 'A', '5537']