Likewise. I was thinking that it'd be about a rich European nation. I was very surprised because Japan is tiny in area; it's smaller than Montana.
Another fun population fact: there are about 250 million people in Indonesia.
Making it the largest Muslim country in the world.
(Before learning this fact, Indonesia wasn't even on my radar when discussing Islam. It's quite moderate, so it rarely makes the news.)
There's a lot of background mess in our mental pictures of the world. We try and be accurate on important issues, but a whole lot of the less important stuff we pick up from the media, the movies, and random impressions. And once these impressions are in our mental pictures, they just don't go away - until we find a fact that causes us to say "huh", and reassess.
Here are three facts that have caused that "huh" in me, recently, and completely rearranged minor parts of my mental map. I'm sharing them here, because that experience is a valuable one.