1000000009
This number is a prime.
1000000007 and 1000000009 are the largest known pair of twin primes of the form [10^n + 7, 10^n + 9].
The smallest emirp of the form 10^n + n (n=9). [Loungrides]
The larger member of the first twimirp greater than a
billion. [Green]
(There are 4 curios for this number that have not yet been approved by an editor.)
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