# 463

This number is a prime. Divide 463 (a prime) by 595 (a palindrome) to obtain an excellent approximation to the common logarithm of 6. The smallest multidigit prime such that both the sum of digits and product of digits of its square remain square. [Russo] 463 meters is exactly one-fourth of an international nautical mile. [Honaker] The entry to the Duomo in Florence, from the Porta della Mandorla on the north side of the Cattedrale di S. Maria del Fiore, contains exactly 463 steps. 463 on a cell phone is the numbers pressed to spell God. [Gregor] The first prime whose digits form a scalene triangle with the smallest prime perimeter. [Beedassy] The first in the smallest set of 7 consecutive primes (463, 467, 479, 487, 491, 499, 503) that are congruent to 3 (mod 4). [Post] There is a 4-6-3 double play in baseball. [Homewood] A 463-tuple would be an "interesting constellation." 463!/463#+1 is the largest non-titanic quasi-compositorial prime of form p!/p#+1. [Loungrides] The only distinct-digit 3-digit prime which remains a prime after a prime digit is subtracted from any of its digits or from all of its digits simultaneously, i.e., 263, 443, 461, 241. [Loungrides] The smallest prime number that is the sum of divisors of an abundant number (392). [Gaydos]

(There are 6 curios for this number that have not yet been approved by an editor.)