Math

# When You Shuffle A Deck Of Cards, You're Creating Something Entirely Unique

It's hard to believe, but if you shuffle a deck of cards well, you're most likely putting them in an order that the universe has never seen before. This is because there are 52! ways to arrange a deck of 52 cards, and 52! is a mind-bogglingly large number. It's more than the number of atoms on Earth, and more than the number of seconds that have elapsed since the universe came into being 13.8 billion years ago. Learn everything you need to know about shuffling a deck with these videos.

– Vsauce

### Key Facts In This Video

1. If you divide a deck of card exactly in half, there will always be exactly as many red cards in one pile as black cards in the other. 03:20

2. The amount of possible combinations for a deck of 52 cards is 52 factorial. An incredibly massive number. 14:16

3. See an amazing illustration of just how big 52 factorial is. 16:03

#### The Best Ways To Shuffle

Are you an overhand shuffler? Or a riffler?

– Numberphile

### Key Facts In This Video

1. It takes about 10,000 overhand shuffles to mix up a deck of cards so that their order is unpredictable. 00:43

2. There are (52!) possible arrangements of cards in a deck of 52 playing cards, a huge number that is also called "52 shriek." 02:07

3. If you riffle shuffle a deck of cards only 5 or 6 times, someone can still make money against you in a card-guessing experiment. 08:32

#### What Is A Perfect Shuffle?

Watch it in action during this crazy card trick.

– Numberphile
Curiosity Staff