9000000001

This number is a prime.

+ 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.

+ The only non-titanic generalized Cullen emirp of the form p=n*10^n+1. [Loungrides]

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