## Sunday, January 25, 2015

### Largest Known Prime

1/25/2015

The largest known prime was discovered two years ago by Curtis Cooper.

It is a Mersenne Prime, 2^57,885,161 - 1.

When written in decimal form it is 17,425,170 digits long.

Of course it would be impossible to determine if a number that large is prime or not with out the use of a computer - well, in this case a bunch of computers.  When mathematicians are working on a project like this they are in competition with others for find another large prime to become the next "worlds largest known prime", but they are also competing in the world of computer science to test their algorithms for finding large prime numbers.

Because of this I have challenged myself to memorize this prime number in its binary form (because the computers that verified its "primeness" work in binary.

In binary it is 57,885,161 digits long.  And today I have finished memorizing all of them.  See below:

Wait for it!

Wait for it!

All 57,885,161 digits are "1".

Sometimes I even amaze myself.

David