The book is now available! 347
(another Prime Pages' Curiosity)
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+ The number of minesweepers that supported the D-Day convoys in World War II.

+ The smallest prime such that the product of its digits is equal to 2 times the number of digits times the sum of digits. [Russo]

+ The largest three-digit prime which remains prime when 2 is added to any of its digits, i.e., 547, 367, and 349, are primes. [Opao]

+ Strobogrammatic primes on a calculator do not contain the digits 3, 4, or 7.

+ The fictitional street number of Dracula's London house (347 Piccadilly) according to Leslie S. Klinger's book The New Annotated Dracula. [Post]

+ The smallest Friedman emirp. [Beedassy]

+ The largest prime factor of 1!+2!+3!+4!+5!+6!+7!+8!+9!. [Upadhyay]

+ There are exactly 347 even digits before the 347th odd digit of pi. (347 is the smallest prime making the previous statement true.) [Keith]

+ 2^2*3^3*7^7*347^347-1 is the largest non-titanic prime of form 2^2*3^3*7^7*347^347*...* a(n-1)^a(n-1)*a(n)^a(n)-1, where n, a(n) and 2^2*3^3*...*a(n)^a(n) – 1 are prime, a(n)>a(n-1), and a(n) is minimal. Note that the previous such primes are: a(1) = 2^2-1 = 3, a(2) = 2^2*3^3-1 = 107, a(3) = 2^2*3^3*7^7*-1 = 88942643. [Loungrides]

+ Number of chess games that end in checkmate after a half dozen plies.

(There are 4 curios for this number that have not yet been approved by an editor.)

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