jQuery increment value of <span> tag

I have a number in a span tag. I need to get the value of the number in the span and then increment it inside jQuery. I know how to do this for a text input - can this be done to a span tag?

SPAN tag

<span class="changeNumber"> 33 </span>

jQuery span selector

var commentNumAppend = $(this).closest(".songContainer").find(".changeNumber");