Is there a real 1000000000 bill?

There is no such thing as a real US $1,000,000,000 (one billion dollar) bill. However, there are some currencies that have issued banknotes of one billion or more of their currency units. The Weimar Republic in Germany issued 100 trillion Mark bills (100,000,000,000,000 Marks), and just after World War II Hungary issued banknotes in the amount of 100,000,000,000,000,000,000 (100 quintillion) pengo.