XXXIX
   HOME

TheInfoList



Click Here for Items Related To - XXXIX
OR:
XXXIX on:   [Wikipedia]   [Google]   [Amazon]

39 (thirty-nine) is the
natural number In mathematics, the natural numbers are the numbers 0, 1, 2, 3, and so on, possibly excluding 0. Some start counting with 0, defining the natural numbers as the non-negative integers , while others start with 1, defining them as the positive in ...
following 38 and preceding 40.


In mathematics

*39 is the 12th distinct
semiprime In mathematics, a semiprime is a natural number that is the product of exactly two prime numbers. The two primes in the product may equal each other, so the semiprimes include the squares of prime numbers. Because there are infinitely many prime n ...
and the 4th in the (3.q) family. It is the last member of the third distinct semiprime pair ( 38,39). *39 has an
aliquot sum In number theory, the aliquot sum of a positive integer is the sum of all proper divisors of , that is, all divisors of other than itself. That is, s(n)=\sum_ d \, . It can be used to characterize the prime numbers, perfect numbers, sociabl ...
of 17, which is a prime. 39 is the 4th member of the 17-aliquot tree within an
aliquot sequence In mathematics, an aliquot sequence is a sequence of positive integers in which each term is the sum of the proper divisors of the previous term. If the sequence reaches the number 1, it ends, since the sum of the proper divisors of 1 is 0. Def ...
of one composite numbers (39, 17, 1,0) to the Prime in the 17-aliquot tree. *It is a
perfect totient number In number theory, a perfect totient number is an integer that is equal to the sum of its iterated totients. That is, one applies the totient function to a number ''n'', apply it again to the resulting totient, and so on, until the number 1 is rea ...
. *39 is the sum of five consecutive
primes A prime number (or a prime) is a natural number greater than 1 that is not a product of two smaller natural numbers. A natural number greater than 1 that is not prime is called a composite number. For example, 5 is prime because the only ways ...
(3 + 5 + 7 + 11 + 13) and also is the product of the first and the last of those consecutive primes. Among small semiprimes only three other integers (10, 155, and 371) share this attribute. 39 also is the sum of the first three powers of 3 (3 + 3 + 3). Given 39, the
Mertens function In number theory, the Mertens function is defined for all positive integers ''n'' as : M(n) = \sum_^n \mu(k), where \mu(k) is the Möbius function. The function is named in honour of Franz Mertens. This definition can be extended to positive r ...
returns 0. *39 is the smallest natural number which has three partitions into three parts which all give the same product when multiplied: , , . *39 is a
Perrin number In mathematics, the Perrin numbers are a doubly infinite constant-recursive sequence, constant-recursive integer sequence with Characteristic equation (calculus), characteristic equation . The Perrin numbers, named after the French engineer , bear ...
, coming after 17, 22, 29 (it is the sum of the first two mentioned). *Since the greatest prime factor of 392 + 1 = 1522 is 761, which is more than 39 twice, 39 is a Størmer number. *The F26A graph is a
symmetric graph In the mathematical field of graph theory, a graph is symmetric or arc-transitive if, given any two ordered pairs of adjacent vertices (u_1,v_1) and (u_2,v_2) of , there is an automorphism :f : V(G) \rightarrow V(G) such that :f(u_1) = u_2 a ...
with 39 edges.


In other fields


Arts and entertainment

*
Japanese wordplay Japanese wordplay relies on the nuances of the Japanese language and Japanese script for humorous effect, functioning somewhat like a cross between a pun and a spoonerism. Double entendres have a rich history in Japanese entertainment (such as ...
and slang: **Through numeric substitution, 39 is the Internet chat slang term for "Thank you" when written with numbers: and . **39 has also been associated with the virtual singer
Hatsune Miku , officially code-named CV01, is a Vocaloid software voicebank developed by Crypton Future Media. Its official mascot is depicted as a sixteen-year-old girl with long, turquoise twintails. Miku's personification has been marketed as a virt ...
for the same reason: can also be read as , and can also be read as . Thus, if using the alternative readings, can also be read as .


History

*In
Afghanistan Afghanistan, officially the Islamic Emirate of Afghanistan, is a landlocked country located at the crossroads of Central Asia and South Asia. It is bordered by Pakistan to the Durand Line, east and south, Iran to the Afghanistan–Iran borde ...
, the number 39 is considered unlucky, due to the belief that it is associated with
pimp Procuring, pimping, or pandering is the facilitation or provision of a prostitute or other sex worker in the arrangement of a sex act with a customer. A procurer, colloquially called a pimp (if male) or a madam (if female, though the term "pimp" ...
s. See
Curse of 39 The curse of 39, also referred to as triakontenneaphobia, is the fear of the number 39. In some parts of Afghanistan, the number is considered to be cursed or a badge of shame as it is purportedly linked with prostitution. Origin The origin of ...
.


References

{{Integers, zero Integers