What does this symbol and number mean?
See my screenshot - What does the tower symbol mean in the bottom left? And/or how is it different from the symbol in the top right? I know the top right symbol and number means how many floors you have, but the symbol and number in the bottom left is clearly different...
The numbers at the bottom: Mine in the far left one and I have 17 floors. My friend is the middle one, and he has 40+ floors...
It still means the number of floors you each have. It doesn't automatically sync every time you look at that page - I have had it be behind as much as 5 floors early on when I was building a lot. I suspect it only syncs a certain number of times per day.
As for your friend - there may be a problem with him syncing - perhaps he isn't connecting to Game Center, or has been offline when it is syncing, so you wouldn't see his floors. I know that sometimes it takes a couple of days for that screen to match what I see when I view my friend's towers, or for it to match how many floors their game says they have.
The top right is how many floors YOU have. The others are your friends. But i think you are tryig to say the one with 13 is yours, yet it says you have 17. I don't know what that means though. Sorry :3