This is the best prime number verification program I have run into. Kudos to the author for making this available for free one both major platforms OS X and Linux.
There are cosmetic reasons for not offering a five-star rating, but I'm overly picky about ease-of-use in human interface design ;-)
This is again a very useful little program for clarifing a typical question in numbertheory. And the developer allows big integers and not only the usual small ones. Thank you!