9645 = 3 x 5 x 643.
9645 is 302040 in base 5. It is 22655 in base 8.
9645 is the number of partitions of 50 such that (greatest part) - (least part) = number of parts (A237832).
9645 is a member of the sequence in which the next term is the sum of the previous term and the square of the sum of its decimal digits, starting with 10 (A112787).