29
This number is a prime.
Just showing those entries submitted by 'Bergot': (Click here to show all)
29 = (2*7) + (3*5), i.e., the first n primes placed in product pairs whereas the first factors are increasing and the second factors are decreasing, then added together. Can you find the next prime with this property? [Bergot]
The reversal of 29 is divisible by the preceding prime (23). [Bergot]
(There is one curio for this number that has not yet been approved by an editor.)
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