This game is kind of like king of the hill, except the "king" is whoever holds the record for biggest number defined.
To keep things under control there are some rules
Your number...
1. Must be a positive integer (FYI, anything with infinite digits is not an integer)
2. Must have a fixed value (eg. "one more than the biggest number anyone else posts" is not allowed*)
3. Must be expressed in fewer than 200 characters (eg. no spamming digits)
4. Cannot use any numbers already assigned a special name by mathematics (eg. "Graham's number" cannot be used when defining your number)
Other than that, you are free to write whatever you want to describe your number.
*You can reference anything you want that doesn't break rule #4, but it has be something that won't change as the game progresses. For example, "the diameter of the earth in millimeters" is okay, since someone can look up the diameter of the earth and calculate that number regardless what is posted afterwards.
Please provide a link to back up your references. Like if you say "number of galaxies in the universe", link to a page with an estimate of that number.
9999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999999
^That is 199 characters worth of 9s