All about flooble | fun stuff | Get a free chatterbox | Free JavaScript | Avatars    
perplexus dot info

Home > Numbers
Inverted Primes (Posted on 2006-12-15) Difficulty: 4 of 5
In the window of my pocket calculator, I can see a six-figure number, abcdef, with distinct digits between 1 and 9. A close inspection of the digits reveals that abcdef, cdef, and def are all prime numbers.

If I turn the calculator upside-down, I see that uvwxyz and wxyz are also prime numbers.

Which number is displayed in the window of my pocket calculator and what is the upside-down version of it?

Full credit for this problem goes to Ajit Athle who has very kindly given his permission for the puzzle to be posted here.

See The Solution Submitted by Josie Faulkner    
Rating: 3.7778 (9 votes)

Comments: ( You must be logged in to post comments.)
  Subject Author Date
Solutionsolution without computer programming or internet search or excel (LOL)jduval2007-05-30 16:26:46
SolutionSolution without Computer Programming (spoiler)Dej Mar2006-12-15 14:03:35
re: Solution without Internet search or ExcelLeming2006-12-15 11:40:57
SolutionSolution without Internet search or ExcelCharlie2006-12-15 11:15:45
SolutionSolution (spoiler)Leming2006-12-15 10:51:06
Some Thoughtsnot a SolutionLeming2006-12-15 10:23:28
Please log in:
Remember me:
Sign up! | Forgot password

Search body:
Forums (0)
Newest Problems
Random Problem
FAQ | About This Site
Site Statistics
New Comments (2)
Unsolved Problems
Top Rated Problems
This month's top
Most Commented On

Copyright © 2002 - 2018 by Animus Pactum Consulting. All rights reserved. Privacy Information