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 are 2 curios for this number that have not yet been approved by an editor.)

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