2223757
This number is a prime.
The smallest prime-digit Honaker prime p containing all of
the prime digits {2, 3, 5, 7} such that (p^n + k) is prime
where k is an integer formed by concatenating in ascending
order the first n digits d, d times each of them, (case
n=8), i.e., 2223757^8 +
122333444455555666666777777788888888. [Bajpai]
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