1087

This number is a prime.

+ 1087 is a prime factor of the 32nd Lucas number (the first such number with index of form 2^n that is composite).

+ The largest known number such that (10000^n+1)/10001 is a probable prime.

+ The smallest prime of the form Rm-m!, i.e., 1111-4! = 1087. [Loungrides]

+ The only 4-digit Kynea prime. [Loungrides]

+ The smallest distinct-digit 4-digit prime such that one digit is equal to the sum of the other digits. [Loungrides]

+ The smallest prime whose square does not divide at least one ten-digit pandigital number. [Gaydos]

+ 1087 + 6^n is prime for n = 1 to 8. [Petrov]

+ Records show that London (England) was burnt down eight times before the most famous fire of London in 1666. The only prime year of those conflagrations was 1087.

(There is one curio for this number that has not yet been approved by an editor.)

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