Leo the Lion and Zara the Zebra are going up a staircase with a certain number of steps. Leo goes four steps up with each jump (though if necessary, he will just jump the last step). Zara goes nine steps up with each jump (though if necessary, she will just jump the last steps if there are fewer than 9 steps left). Suppose that Zara takes 15 fewer jumps than Leo to reach the top of the staircase. Let $s$ denote the sum of all possible numbers of steps this staircase can have. What is the sum of the digits of $s$?