The book is now available! 2221
(another Prime Pages' Curiosity)
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+ 2221 and 22221 - 22212 are both prime. [Luhn]

+ The next prime happy-go-lucky year will be 2221. The number 2221 is simultaneously a happy number and a lucky number.

+ The smallest prime such that if reduced by one, has 1, 2 and 3-digit factors. [Gallardo]

+ 2221 = 1^2 + 1^3 + 2^5 + 3^7 is the sum of the first 4 positive Fibonacci numbers raised to the powers of the first 4 primes. Curiously, it is concatenated from entirely Fibonacci number digits. Note that 2221 is prime. [Post]

+ The number of positive-integer Proximate-Prime Polynomials derived from 4 successive primes under 1000000. [Capelle]

+ The smallest Honaker prime formed by concatenating two consecutive numbers. [Loungrides]

+ The smallest prime formed from two successive double-digit composite numbers. [Loungrides]

+ The smallest Honaker prime with sum of digits equal to 7. Are there any more? [Gaydos]

+ The smallest Honaker prime with no digits greater than 2. The next one is 22221211. [Gaydos]

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




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