The book is now available! 9000000001
(another Prime Pages' Curiosity)
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+ The largest 10-digit prime with sum of digits equal to 10. Note that it is also the reverse of the smallest such number (1000000009). [Necula]

+ 9000000001, 9900000001, 9990000001, and 9999000001 are each prime; but unfortunately, 9999900001 is composite.

(There is one curio for this number that has not yet been approved by an editor.)

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