Show your work. Business Insider says it's true, though. Which means it's probably false. Except maybe they made a mistake in their calculations and accidentally printed something that is true. But is that really possible? They also have a text list, which I think is ordered by population though I can't really tell. But half the population of the US is squeezed into just these spaces?
Then again, persquaremile.com says the whole world's population could fit into these areas if various degrees of density are allowed for: