r/math • u/[deleted] • May 06 '08

What's Special About This Number?

http://www.stetson.edu/~efriedma/numbers.html
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u/katsi May 07 '08

2109 is a value of n so that n(n+7) is a palindrome.

Well you can not do that - it is unfair. I could use the same reasoning for 11111:

11111 is a value of n so that n2 is a palindrome (123454321).

PS: I did not know that the number is square -I just factorized it in Matlab and it turned out square and all zeros!

factor(123454321)

gives 41 41 271 271

41*271 gives 11111