2019

This number is a composite.

+ New Year's Eve 2019 will be a prime number day of form yyyymmdd.

+ No, this year isn't what a prime curiologist would prefer it would be. Please check back in 2027.

+ The smallest number (also a semiprime) that can be written in six ways as the sum of the squares of three primes. Can you find one or more of the examples?

+ 2019^2^(9-1-0-2)-2018 is prime and sod(2019^2^(9-1-0-2)-2018) is an emirp [Sariyar]

+ 2019 is a semiprime (3*673) but the concatenation of its factors in the two possible ways are primes: 3673 and 6733. [Rivera]

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