The value of a pound of $50 bills is $22,700. Every U.S. bill, no matter how much it is worth, weighs about 1 gramme. Since a pound is made up of 454 grammes, a pound of any U.S. bill is worth 454 times its face value.
Since each U.S. banknote has the same weight of 1 gramme, they can be used to calibrate scales when none are available.
The $100,000 Gold Certificate was the most money that the U.S. Bureau of Engraving and Printing ever made, but it was only made for transactions between Federal Reserve banks.
The paper used for U.S. currency is made of 75% cotton and 25% linen. It is strong enough to withstand about 4,000 double folds before it tears.