127

This number is a prime.

Just showing those entries submitted by 'Gaydos': (Click here to show all)

+ The largest sum of digits of the square of a distinct digit brilliant number (924107563^2 = 853974787993798969 and 948302567^2 = 899277758578789489). [Gaydos]

+ The sum of reversals of the first five squares (1+4+9+61+52) as well as the sum of the reversals of the first four cubes (1+8+72+46). [Gaydos]

+ 2^127 plus its reverse is a prime number. [Gaydos]

+ There are 127 possible prime U.S. Zip Codes that contain exactly two different digits (from 00002 to 99991). [Gaydos]

+ There are 127 distinct-digit primes for which subtracting the prime index produces an anagram of the prime. [Gaydos]

+ The smallest non-palindromic prime that has the same Collatz trajectory length (46) as its reversal (721). [Gaydos]

+ The 127th prime number (709) and the 127th happy number (907) are an emirp pair. [Gaydos]

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

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