939
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- yes
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 1256
- Proper Divisor Sum (Aliquot Sum)
- 317
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 624
- Möbius Function
- 1
- Radical
- 939
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- no
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- no
- Lucas Number
- no
- Tetrahedral Number
- no
- Pell Number
- no
- Tribonacci Number
- no
- Pronic Number
- no
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 85
- Smith Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- Prime Power
- no
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Names
- German
- neunhundertneununddreißig· ordinal: neunhundertneununddreißigste
- English
- nine hundred thirty-nine· ordinal: nine hundred thirty-ninth
- Spanish
- novecientos treinta y nueve· ordinal: 939º
- French
- neuf cent trente-neuf· ordinal: neuf cent trente-neufième
- Italian
- novecentotrentanove· ordinal: 939º
- Latin
- nongenti triginta novem· ordinal: 939.
- Portuguese
- novecentos e trinta e nove· ordinal: 939º
Appears in sequences
- Numbers k such that 3^k, 3^(k+1) and 3^(k+2) have the same number of digits.at n=43A001682
- Numbers k such that 9*2^k - 1 is prime.at n=18A002236
- Coefficients in expansion of permanent of infinite tridiagonal matrix shown below.at n=44A003113
- a(n) = floor(n*phi^8), where phi is the golden ratio, A001622.at n=20A004923
- a(n) = a(n-1) + a(n-9) for n >= 9; a(n) = 1 for n=0..7; a(8) = 2.at n=39A005711
- Numbers k such that phi(k) = phi(sigma(k)).at n=38A006872
- Coordination sequence T5 for Zeolite Code AET.at n=21A008011
- Coordination sequence T3 for Zeolite Code BRE.at n=20A008060
- Coordination sequence T5 for Zeolite Code EUO.at n=19A008100
- Expansion of (1+x^7)/((1-x)*(1-x^2)*(1-x^3)*(1-x^4)).at n=39A008768
- Coordination sequence T2 for Zeolite Code VNI.at n=19A009908
- Coordination sequence T5 for Zeolite Code VNI.at n=19A009911
- a(n) = -1 + Sum_{i=1..n} phi(i).at n=54A015614
- Expansion of 1/(1 - x^9 - x^10 - ...).at n=49A017903
- Cycle class sequence c(2n) (the number of true cycles of length 2n in which a certain node is included) for zeolite EAB = TMA-E (Aiello and Barrer)(1) (Me4N)2Na7[Al9Si27O7] starting with a T1 atom.at n=4A019011
- Fibonacci sequence beginning 1, 27.at n=9A022397
- Convolution of natural numbers >= 2 and A023532.at n=46A023547
- Convolution of (F(2), F(3), F(4), ...) and odd numbers.at n=9A023652
- Numbers with exactly 3 2's in base 5 expansion.at n=25A023732
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n+1-k), where k = [ (n+1)/2 ], s = (F(2), F(3), ...), t = (odd natural numbers).at n=13A024592