773

This number is a prime.

+ The only three-digit iccanobiF prime.

+ The largest three-digit unholey prime.

+ Replacing each digit of prime 773 with its square respectively its cube results in two new primes 49499 and 34334327. Note that this latter number is also an emirp (72343343). [De Geest]

+ The largest three-digit prime-digit prime. [Fellows]

+ The number 3 followed by 773 7's is prime. [De Geest]

+ The smallest prime such that adding a preceding or trailing digit will always result in a composite if we omit the case where the leading digit is zero. [Noll]

+ This prime is the sum of the number of 3-dimensional faces in one each of the 6 regular 4-dimensional polytopes: 5 + 8 + 16 + 24 + 120 + 600 = 773. (Equivalently, this prime is the sum of the number of vertices, i.e., 0-dimensional faces, in one each of the 6 regular 4-dimensional polytopes.) [Post]

+ The smallest odd number n where n + 2k is composite for all k < n. [Gudipati]

+ The only 3-digit prime p such that p +/- 666 are emirps. [Loungrides]

+ In binary 11011 + 2, 110011 + 2, 1100011 + 2, 11000011 + 2, 110000011 + 2 and 1100000011 + 2 are all prime, this one being the largest. Note that all the primes are full reptend primes in binary. [Homewood]

(There are 5 curios for this number that have not yet been approved by an editor.)

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