1) The human brain has a storage capacity equivalent to around 2.5 petabytes, which is roughly equivalent to three million hours of TV shows.

2) The Earth's core is hotter than the surface of the Sun.

3) Bats are the only mammals capable of sustained flight.

4) J.K. Rowling's "Harry Potter" series of books has sold over 500 million copies worldwide and has been translated into 80 languages.