Is 1031 a prime number

Yes. It is a Prime number It is also an emirp (i.e.1301 is prime). And if you want to amaze friends by offering to write out from memory a prime with over a thousand digits, simply write the digit ' 1 ' 1031 times; this is the largest repunit (repeated digit) proven prime.[[User:Colcestrian|Colcestrian]] 02:43, 23 Jun 2009 (UTC)