The number 21982145917308330487013369 is the thirteenth power of a natural number. Find the number using just pen and paper.

(In reply to why d1 .?...spoiler by Ady TZIDON)

Well dixi maybe, but this has been a UC Berkeley problem before (in the early 80s). It may be that Sengupta's method is canonical. I don't know much about logs and slide rules, but it is a fact that log(10) 89 is 1.94939000... and I suspected that this might have something to do with why 89 was chosen.

Edited on January 12, 2013, 12:52 pm

Posted by broll on 2013-01-12 12:44:01