## 10 points

Factor the number 9999598404017903

Hint #1: It has two factors.

Hint #2: Both factors contain a 9999 somewhere in them.

EDIT: Orginal Number was copied incorrectly, as Jenks noted (the last digit was a 4, should have been a 3). It is corrected now. I am subtracting 2 points from my score for posting an even number and not catching the fact that an even number might have a few more than 2 factors.

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Really? Just two factors?

TheJenksster said this on August 21, 2008 at 11:33 am |

Huh?

In mathematics, factorization (also factorisation in British English) or factoring is the decomposition of an object (for example, a number, a polynomial, or a matrix) into a product of other objects, or factors.

http://en.wikipedia.org/wiki/Factorization

wcuk said this on August 21, 2008 at 11:39 am |

99997873; 99998111

Brute-forcing my way up the standings!

Charlie said this on August 21, 2008 at 4:09 pm |

Winner winner, chicken dinner!

wcuk said this on August 21, 2008 at 4:10 pm |

Oh, reasoning:

the sqrt of your number was just below 99997992. So, 99997992 squared is just larger than your number. I added and subtracted equal quantities from 99997992, until their product descended from 9999598404032064 to 9999598404017903.

Note: one needs a high-precision calculator to perform operations on numbers this large.

Charlie said this on August 21, 2008 at 4:18 pm |

Charlie, does the Windows calculator in scientific mode fit the bill?

theJenksster said this on August 22, 2008 at 7:14 am |

To test if it works, just multiply the two factors and see if you get 9999598404017903 to full precision. Most likely, you will get 9.999598404*10^15. On one improved calculator that I used, I got a rounding error and found 9999598404017904. I found a high precision Javascript calculator at http://www.petting-zoo.org/Calculator.html

Don’t ask me what high precision calculations have to do with a petting zoo… It is a strange, strange, world that we live in!

Charlie said this on August 22, 2008 at 9:37 am |