Each month, we will post a new Challenge Problem for you to attempt. If you submit the correct answer, you will be entered into that month’s drawing for a free Manhattan GMAT Prep item. Tell your friends to get out their scrap paper and start solving!

Note We email the winner directly every month, and provided we then receive consent from the winner we post his or her name on our Facebook Fan Page .

Good luck! These are tough problems!

This Month's Problem: "Can you find the GCF?"

If n is a positive integer, what is the greatest common factor of n and 64?
 
(1) No two different factors of n sum to a prime number.
 
(2) The greatest common factor of n and 2,310 is 165.

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