The highest named number is the Googolplexian: A "1" followed by a googolplex of zeros.
To understand this magnitude you need to know that a Googolplex is a "1" followed by a googol of zeros, and that at a Googol is a "1" followed by one hundred zeros.
The highest number which is not defined as to magnitude is infinity.
Google Plex
the high number 1638478953
It is not known to man because that number range is infinite.
The highest number of plastic surgeries in the world.
nine
A GOOGLE.....
It is the highest number known. It has about 100 googl in it.
The highest number of plastic surgeries in the world.
As of February 2013, the largest known prime number is 2^57,885,161 − 1, a number with 17,425,170 digits.
Trillquadquintsexsepoctnondecundecduo...That's the highest number known to mankind
It doesn't make much sense to talk about the "highest number", or about the "highest number known to man", since there are infinitely many numbers. In the case of a finite number, you can always add one to get a higher number. In the case of an infinite number, you can always raise 2 to the power of this infinite number to get a higher infinity.
There isn't one... Think of a number and name it after yourself ;)