Only those with lots of money can afford a summer beach house.

Want a crazy statistic? About 5% of all Americans are millionaires. Think about that for a second: If you had 20 kids in your middle school homeroom, then at least one of them is probably a millionaire. Graduate from high school with a class of 500? About 25 of them are likely worth at least seven figures.

According to the Global Wealth Survey conducted at Credit Suisse, there are almost 15.7 million millionaires in the United States -- by far the most in the world. The U.K. comes in next with about 2.4 million millionaires.

The folks over at Statista wanted to show just how wealthy the United States was compared to the rest of the world, so they made this infograph:

But there's a problem with this data: It doesn't take into consideration the population of the country. The United States, while relatively wealthy, is the third-largest country in the world in terms of population. It's pretty easy for us to have the most millionaires, especially when China and India -- the two largest -- are nowhere near as wealthy on a per-capita basis.

So I went back through the data and found that the United States is nowhere near the wealthiest when you consider the relative wealth of all its citizens. In fact, the country that claims that distinction has roughly 70% more millionaires, adjusted for population, than the U.S.

The slideshow below runs through the top 10 countries in the world in terms of millionaires per 1 million citizens. The results may surprise you.

The 10 Countries with the Most Millionaires from The Motley Fool.