347
This number is a prime.
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 π. (347 is the smallest prime making the previous
statement true.) [Keith]
The only non-titanic-prime (emirp) of form 7^p+(p+1) for p a prime, (p=3). [Loungrides]
(347, 743) is the first pair of emirps (p, q) such that 5^p
and 5^q are both "apocalyptic numbers", i.e., numbers that
contain the beast number. [Loungrides]
Number of chess games that end in checkmate after a half-dozen plies.
Shula's 347 Grill serves up prime cuts in a contemporary
setting with sports photos on the walls.
There are 347 five-digit Honaker primes. [Gaydos]
On November 24, 2018, Yusheng Du (杜宇生) broke the world
record fastest time to solve a 3x3 Rubik's cube. He solved
it in 3.47 seconds. [Apdos]
The only emirp that can be represented as the number of lines in a Rhapsody of Homer’s Odyssey, (i.e. Rhapsody VΙI). This line says: «πὰρ δὲ γυνὴ δέσποινα λέχος πόρσυνε καὶ εὐνήν». [Loungrides]
The smallest prime number for which the sum of the squares
of the digits of its square equals the sum of the squares
of the digits of the square of its prime index. [Gaydos]
Apple Brandy Prime Cuts is a custom, USDA inspected abattoir for farmers and meat handlers located on 347 Thomas Street in North Wilkesboro, NC. [Ashley]
(347, 349, 353, 359, 367) is the first case of five
successive primes whose the differences of successive
primes in order are: 2, 4, 6, 8. [Loungrides]
H.B. Gibson, in his book Hypnosis: Its Nature and
Therapeutic Uses, says the record period for a chicken
remaining in hypnosis is 3 hours 47 minutes.
Open question: Does any repunit semiprime with prime length (Rp), e.g., R347, divisible by 2*p+1 exist? [Xayah]
The smallest prime Yarborough number that has the same sum
of digits (14) as its Yarborough indext (158). [Gaydos]
The 347th decade (3460 to 3469) contains 4 prime
numbers: 3461, 3463, 3467 and 3469. [Prisacariu]