911

This number is a prime.

+ 9-1-1 is the prime phone number in the United States to dial in case of emergency.

+ The Porsche 911 is an awesome, high-speed sports car. [Job]

+ On the first anniversary of the 9/11 terrorist attacks in New York City, the numbers that popped up for the New York Lottery were 9-1-1. [MSN]

+ The Madrid Attack came 911 days after 9/11.

+ The 9/11 terrorist attacks in New York City occurred on the 254th day of the year. 1609 is the 254th prime number. Note that explorer Henry Hudson first came across the island of Manhattan on 9/11/1609. [Lewis]

+ Consider a Fibonacci-like sequence starting with 9, 11. The 11th term will be 911.

+ The smallest prime obtained by concatenating the product and the sum of its own digits. [Silva]

+ Consider the integers formed from the ordered permutations of all distinct positive digits up to 9. Term 11 (i.e., 123457968) is the first to fall between a twin prime pair.

+ 911 is not only a centered decagonal prime, it is also the sum of three consecutive irregular primes (293, 307, and 311). [Green]

+ The first of nine consecutive primes such that each remain prime if you eliminate the first digit: (911, 919, 929, 937, 941, 947, 953, 967, 971). [Loungrides]

+ According to the U.S. Decennial Census, the population of Honaker, Virginia was 911 in 1970.

+ Enniakosioihendecaphobia is the fear of 911.

+ There are 911 distinct-digit primes between 951^3 and 952^3. The most for any pair of consecutive cubes. [Gaydos]

+ If you start a sequence with 2, where each additional term is the next prime after reversal of the previous term, then 911 is the first term to repeat: 2, 3, 5, 7, 11, 13, 37, 79, 101, 103, 307, 709, 911, 127, 727, 733, 347, 751, 163, 367, 769, 971, 181, 191, 193, 397, 797, 809, 911. [Gaydos]

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

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