Australia' central bank has an answer to this as it prints one of the most advanced currencies in the world.
The nation's banknotes are totally waterproof, hard to counterfeit and relatively cleaner because they are resistant to moisture and dirt.
Just wash it in the kitchen with tap water, wipe it and voila! it's as good as new.
As these are polymer banknotes, which has a waxy feeling compared to regular notes made of cotton fiber paper, they tend to last two to three times longer than the normal ones.
This feature extends the life of every dollar bill, without any extra replacement costs.
