Allows you to hide only the total follower count on the Tumblr Activity page. To hide it only on your main blog so it still shows up on any side blogs you have, just change "YOUR-USERNAME-HERE" to your own username in the "Applies to" field in Stylish. To hide follower count on all your blogs, insert https://www.tumblr.com/ instead.

NOTE: Tumblr just changed the URL for the activity page, so it should now look like this:
https://www.tumblr.com/blog/YOUR-USERNAME-HERE/activity