This number is a prime.
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(223, 227, 229, 233) is the first tetrad of successive primes whose the digits of each prime are complementary of the digits of another tetrad of successive primes, i.e., (887, 883, 881, 877). [Loungrides]
The only 3-digit isolated prime concatenated from two isolated primes, 2 and 23. [Loungrides]