View source for 30,000

{{Infobox number|number = 30000}}
'''30,000''' ('''thirty thousand''') is the [[natural number]] that comes after 29,999 and before 30,001.

==Selected numbers in the range 30001–39999==

===30001 to 30999===
* '''30029''' = [[primorial prime]]
* '''30030''' = [[primorial]]<ref>{{Cite OEIS|A002110|Primorial numbers}}</ref>
* '''30031''' = smallest [[composite number]] which is one more than a primorial
* '''30203''' = [[safe prime]]
* '''30240''' = [[harmonic divisor number]],<ref name=A001599>{{Cite OEIS|A001599|Harmonic or Ore numbers}}</ref> smallest [[Multiply perfect number|4-perfect number]]<ref name=A007539>{{Cite OEIS|A007539|first n-fold perfect (or n-multiperfect) number}}</ref>
* '''30323''' = [[Sophie Germain prime]] and safe prime
* '''30420''' = pentagonal pyramidal number<ref name=A002411>{{Cite OEIS|A002411|Pentagonal pyramidal numbers}}</ref>
* '''30537''' = [[oeis:A005043|Riordan number]]
* '''30694''' = [[open meandric number]]
* '''30941''' = first base 13 repunit prime

===31000 to 31999===
* '''31116''' = [[octahedral number]]<ref name=A005900>{{Cite OEIS|A005900|Octahedral numbers}}</ref>
* '''31185''' = number of partitions of 39<ref name=A000041>{{cite OEIS|A000041|a(n) is the number of partitions of n (the partition numbers)}}</ref>
* '''31337''' = [[cousin prime]], pronounced ''elite'', an alternate way to spell ''[[Leet|1337]]'', an obfuscated alphabet made with numbers and punctuation, known and used in the [[gamer]], [[Hacker (programmer subculture)|hacker]], and [[Bulletin board system|BBS]] cultures.
* '''31395''' = [[square pyramidal number]]
* '''31397''' = prime number followed by a record [[prime gap]] of 72, the first greater than 52<ref>{{MathWorld|title=Prime Gaps|urlname=PrimeGaps}}</ref>
* '''31688''' = the number of years approximately equal to 1 trillion seconds
* '''31721''' = start of a [[prime quadruplet]]<ref name=A007530>{{Cite OEIS|A007530|Prime quadruples: numbers k such that k, k+2, k+6, k+8 are all prime}}</ref>
* '''31929''' = Zeisel number<ref>{{Cite OEIS|A051015|Zeisel numbers}}</ref>

===32000 to 32999===
* '''32043''' = smallest number whose [[square (algebra)|square]] is [[Pandigital number|pandigital]].
* '''32045''' = can be expressed as a sum of two squares in more ways than any smaller number.<ref>{{Cite OEIS|A088959|Lowest numbers which are d-Pythagorean decomposable, i.e., square is expressible as sum of two positive squares in more ways than for any smaller number}}</ref>
* '''32760''' = harmonic divisor number<ref name=A001599/>
* '''32761''' = 181<sup>2</sup>, [[centered hexagonal number]]
* '''32767''' = 2<sup>15</sup> &minus; 1, largest positive value for a signed ([[two's complement]]) 16-bit [[integer (computer science)|integer on a computer]].
* '''32768''' = 2<sup>15</sup> = 8<sup>5</sup> = 32<sup>3</sup>, maximum [[absolute value]] of a negative value for a signed (two's complement) 16-bit [[integer (computer science)|integer on a computer]].
* '''32800''' = pentagonal pyramidal number<ref name=A002411/>
* '''32993''' = [[Leyland number#Leyland prime|Leyland prime]]<ref>{{Cite OEIS|A094133|Leyland prime numbers}}</ref> using 2 & 15 (2<sup>15</sup> + 15<sup>2</sup>)

===33000 to 33999===
* '''33333''' = [[repdigit]]
* '''33461''' = Pell number,<ref>{{Cite OEIS|A000129|Pell numbers}}</ref> Markov number<ref name=A002559>{{Cite OEIS|A002559|Markoff (or Markov) numbers}}</ref>
* '''33511''' = square pyramidal number
* '''33781''' = octahedral number<ref name=A005900/>

===34000 to 34999===
* '''34560''' = 5 [[superfactorial]]<ref>{{Cite OEIS|A000178|Superfactorials}}</ref>
* '''34790''' = [[oeis:A283877|number of non-isomorphic set-systems]] of weight 13.
* '''34841''' = start of a prime quadruplet<ref name=A007530/>
* '''34969''' = favorite number of the Muppet character [[Count von Count]]<ref>{{cite web|url=https://www.bbc.co.uk/news/magazine-19409960|title=Why was 34,969 Count von Count's magic number?|date=2012-08-30|access-date=2012-08-31|work=BBC News}}</ref>

===35000 to 35999===
* '''35720''' = square pyramidal number
* '''35840''' = number of [[ounce]]s in a [[long ton]] (2,240 [[pound (mass)|pounds]])
* '''35890''' = [[tribonacci number]]<ref>{{Cite OEIS|A000073|Tribonacci numbers}}</ref>
* '''35899''' = [[alternating factorial]]<ref>{{Cite OEIS|A005165|Alternating factorials}}</ref>
* '''35937''' = 33<sup>3</sup>, chiliagonal number<ref>{{Cite OEIS|A195163|1000-gonal numbers}}</ref>
* '''35964''' = [[digit-reassembly number]]

===36000 to 36999===
* '''36100''' = sum of the cubes of the first 19 positive integers
* '''36463''' – number of parallelogram polyominoes with 14 cells<ref>{{cite OEIS|A006958|Number of parallelogram polyominoes with n cells (also called staircase polyominoes, although that term is overused)}}</ref>
* '''36594''' = octahedral number<ref name=A005900/>

===37000 to 37999===
* '''37338''' = number of partitions of 40<ref name=A000041/>
* '''37378''' = [[semi-meandric number]]<ref>{{Cite web|url=https://oeis.org/A000682|title=Sloane's A000682 : Semimeanders|website=The On-Line Encyclopedia of Integer Sequences|publisher=OEIS Foundation|access-date=2016-06-15}}</ref>
* '''37634''' = third term of the [[Lucas–Lehmer primality test|Lucas–Lehmer sequence]]
* '''37666''' = [[Markov number]]<ref name=A002559/>
* '''37926''' = pentagonal pyramidal number<ref name=A002411/>

===38000 to 38999===
* '''38024''' = square pyramidal number
* '''38209''' = n such that n | (3<sup>n</sup> + 5)<ref>{{cite OEIS|A277288|Positive integers n such that n {{!}} (3^n + 5)}}</ref>
* '''38305''' = the largest Forges-compatible number (for index 32) to the field <math>\mathbb{Q}(\sqrt{6}, \sqrt{14})</math>. But a conjecture of [[Viggo Brun]] predicts that there are infinitely many such numbers for any Galois field <math>F</math> unless <math>F</math> is [[Perfect field | bad]].
* '''38416''' = 14<sup>4</sup>
* '''38501''' = 7<sup>4</sup> + 190<sup>2</sup>: Friedlander-Iwaniec prime.<ref>{{cite OEIS|A028916|Friedlander-Iwaniec primes: Primes of form a^2 + b^4}}</ref> Smallest prime separated by at least 40 from the nearest primes (38461 and 38543). It is thus an ''[[isolated prime]]''.<ref>{{cite OEIS|A023186|Lonely (or isolated) primes}}</ref> [[Chen prime]].<ref>{{cite OEIS|A109611|Chen primes: primes p such that p + 2 is either a prime or a semiprime}}</ref>
* '''38807''' = number of non-equivalent ways of expressing 10,000,000 as the sum of two prime numbers<ref>{{Cite OEIS|1=A065577|2=Number of Goldbach partitions of 10^n|access-date=2023-08-31}}</ref>
* '''38962''' = [[Kaprekar number]]<ref>{{Cite OEIS|A006886|Kaprekar numbers}}</ref>

===39000 to 39999===
* '''39299''' = Integer connected with coefficients in expansion of Weierstrass P-function<ref>{{Cite OEIS|A002770|Weierstrass P-function}}</ref>
* '''39304''' = 34<sup>3</sup>
* '''39559''' = octahedral number<ref name=A005900/>
* '''39648''' = tetranacci number<ref>{{Cite OEIS|A000078|Tetranacci numbers}}</ref>

===Primes===
There are 958 prime numbers between 30,000 and 40,000.

== References ==
{{reflist}}

{{Integers|10}}

[[Category:Integers|30000]]