1908
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 18
- Divisor Sum
- 4914
- Proper Divisor Sum (Aliquot Sum)
- 3006
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 624
- Möbius Function
- 0
- Radical
- 318
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 3
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 37
- Smith Number
- yes
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- yes
- Odd
- no
Appears in sequences
- Expansion of 1 / ((1-x)^2*(1-x^2)*(1-x^3)*(1-x^4)).at n=27A002621
- Number of 3-connected self-dual planar graphs with 2n edges.at n=8A002841
- Numbers that are the sum of 11 positive 6th powers.at n=30A003367
- Numbers of Twopins positions.at n=18A005688
- Coordination sequence T4 for Zeolite Code EMT.at n=36A008089
- Coordination sequence T7 for Zeolite Code EUO.at n=27A008102
- Coordination sequence T7 for Zeolite Code MTT.at n=27A008195
- Year of birth of n-th President of U.S.A.at n=35A008745
- Coordination sequence T2 for Zeolite Code AFX.at n=33A009865
- Pisot sequence E(3,11), a(n) = floor(a(n-1)^2/a(n-2) + 1/2).at n=5A010911
- Coefficients in expansion of e as Sum_{n>=1} a(n)/(n*n!*(n+1)!), as found by greedy algorithm.at n=49A011189
- Number of lines through exactly 9 points of an n X n grid of points.at n=55A018816
- Numbers k such that the continued fraction for sqrt(k) has period 24.at n=28A020363
- Sum of distinct prime divisors of prime(n)*prime(n-1) - 1.at n=43A023521
- a(n) = T(2n,n-1), T given by A026648.at n=5A026650
- a(n) = Sum_{k=0..n-1} T(n,k) * T(n,k+1), with T given by A026648.at n=5A026972
- Numbers with 18 divisors.at n=32A030636
- Four times pentagonal numbers: a(n) = 2*n*(3*n-1).at n=18A033579
- Coordination sequence T2 for Zeolite Code CFI.at n=29A033600
- Multiplicity of highest weight (or singular) vectors associated with character chi_131 of Monster module.at n=36A034519