Fortunate number Fortunate number A Fortunate number, named after Reo Fortune, is the smallest integer "m" > 1 such that, for a given positive integer "n", "p"# + "m" is a prime number, where the primorial "p"# is the product of the first "n" prime numbers. For example, to find the seventh Fortunate number, one would first calculate the product of the first seven primes (2, 3, 5, 7, 11, 13 and 17), which is 510510. Adding 2 to that gives another even number, while adding 3 would give another multiple of 3. One would similarly rule out the integers up to
11 (number) 11 (number) 11 (eleven) is the natural number following 10 and preceding 12. It is the first repdigit. In English, it is the smallest positive integer requiring three syllables and the largest prime number with a single-morpheme name. Eleven derives from the Old English ' which is first attested in Bede's late 9th-century "Ecclesiastical History of the English People". It has cognates in every Germanic language (for example, German "elf"), whose Proto-Germanic ancestor has been reconstructed as *"ainalifa-", from the prefix *"aina-" (adjectival "one") and suffix *"-lifa-" of uncertain meaning. It is sometimes compared with the Lithuanian ', although ""