The book is now available! 221
(another Prime Pages' Curiosity)
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+ 2*3*5*7+11=13*17. Note the consecutive use of the first 7 primes. [Rupinski]

+ 221^221 + reversal(221) is prime. It is the only known number greater than 1 with this property. [Firoozbakht]

(There are 2 curios for this number that have not yet been approved by an editor.)

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