108649
This number is a prime.
 The smallest emirp that contains all of the non-prime digits.  [Punches]
 
The smallest emirp that contains all of the non-prime digits.  [Punches]
 The smallest emirp formed from the concatenation of first n
composite numbers, (n=5), i.e., 4, 6, 8, 9 10.  [Loungrides]
 
The smallest emirp formed from the concatenation of first n
composite numbers, (n=5), i.e., 4, 6, 8, 9 10.  [Loungrides]
(There is one curio for this number that has not yet been approved by an editor.)
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