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.
['8501', 'f', 'Z', '2399', 'd', '9837', 'Y', 'c', 'd', 'c', 'f', 'I', '9401', '2691', 'I', 'V', '2725', '6691', '189', '9865']