1889

This number is a prime.

G.C. Chrystal's Algebra (Edinburgh, 1889, vol. ii, p. 159) gives the following amusing fallacy:

The smallest prime such that it and the next 4 primes (1889, 1901, 1907, 1913, 1931) are all equal to 5 (mod 6). [Post]

The year the Wall Street Journal was first published. [Green]

French engineer Gustave Eiffel completed the Eiffel Tower in 1889. [Green]

The year Adolf Hitler was born. [Homewood]

1889 is the average of 23² and 57². Note the prime digits. [Gudipati]

The smallest prime formed by using all the digits which can be digital root of cubic numbers. [Gupta]

William Gray is credited with inventing the coin payphone in 1889. [Homewood]

1889, 18899, 188999, 1889999, and 18899999 are all prime numbers. [Anitha]