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]

+ The first Carol prime, i.e., a prime of form (2^x-1)^2-2, for x a composite, (x=4). Note that 223 is a prime-digit prime. [Loungrides]

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