1187
This number is a prime.
1187 concatenated with either the previous prime (1181) in order or the next prime (1193) in order is prime. This is the smallest 4-digit number with this property. [Mix]
The smallest non-emirp such that the prime factors of its reversal are emirps. [Green]
(There are 4 curios for this number that have not yet been approved by an editor.)
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