The mega-valuable $500, $1,000, $5,000 and $10,000 bills were last printed in 1945 but weren't discontinued until 1969. In reality, these low-demand, ultra-high denomination notes had all but vanished from circulation well before then. Most of them were incinerated by the Mint, but several hundred thousand are thought to exist, and remain legal tender.

Meanwhile, early big bills such as the 1890 Grand Watermelon $1,000 treasury note – so named because of the green zeros on the back – can sell for eye-watering amounts. In 2014, one example fetched a staggering $3.3 million at auction in 2014, making it the world's most valuable banknote.

How America's money has changed over time