Removing Digits

A prime number is a number with only two factors, itself and one (29 for example). Find the largest prime number that remains a prime number when the right most digit is removed until only one digit remains (73 fits this pattern as both 73 and 7 are prime numbers, for example).

– This puzzle was suggested by Paul Cleary

Remember, to solve this puzzle and appear on the leaderboard, email both your solution and your source code (in any language) to Good luck!!

View all puzzles »