This number is a prime.

+ The largest 4-digit left-truncatable prime (emirp). It is also the largest four-digit deletable emirp. Deleting one digit at a time, we take a prime at each step, i.e., 967, 97, 7. Note that 967, 97 are also emirps. [Loungrides]

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

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