# I need cool facts about huge numbers

So, my 5-year-old nephew is obsessed with huge numbers, especially named numbers such as googol, duodecillion, and centillion. The other day I spent some time reciting these numbers to him, and trying (and failing) to describe them. What I need are some cool facts about these numbers, such as "there are 1 quadrillion cat hairs in the world", or "there are not enough stars in the universe to fill one googol".

Besides math, his main interests are super-heroes and, apparently, cars.

I'm not a math or physics guy, so hopefully you guys can help me cheat :P

Here's a video for you :) https://www.youtube.com/watch?v=0X9DYRLmTNY It's a bit advanced for a 5 year old but Numberphile is very accessible so it's more for you than for him.

Here's a video for you :)

It's a bit advanced for a 5 year old but Numberphile is very accessible so it's more for you than for him.

2. psi
(edited )
You/he would probably enjoy Scott Aaronson's classic essay Who can name the biggest number? (this would be a fun game to play with your nephew). To cut to the chase: if you aren't defining your...

You/he would probably enjoy Scott Aaronson's classic essay Who can name the biggest number? (this would be a fun game to play with your nephew). To cut to the chase: if you aren't defining your numbers recursively in terms of the busy beaver function, you aren't going to win. For example, BB(8000) cannot be written down in ZF set theory.

3. Fal
Belphegor’s Prime
4. [2]
Wulfsta
Well, related to this, there are different sizes of infinity. That is a fairly vague way to state this idea, but it’s not unreasonable that a layman can understand Cantor’s diagonalisation....

Well, related to this, there are different sizes of infinity. That is a fairly vague way to state this idea, but it’s not unreasonable that a layman can understand Cantor’s diagonalisation. Numberphile or 3blue1brown probably have a video on this. Might be above a 5 year old though…