1956
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 4592
- Proper Divisor Sum (Aliquot Sum)
- 2636
- 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
- 648
- Möbius Function
- 0
- Radical
- 978
- Omega Function (Ω)
- 4
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 50
- Smith Number
- no
- 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
- 9-gonal (or enneagonal or nonagonal) numbers: a(n) = n*(7*n-5)/2.at n=24A001106
- Expansion of g.f.: (1+x^3)*(1+x^4)/((1-x)*(1-x^2)^2*(1-x^4)).at n=35A004657
- Alkane (or paraffin) numbers l(7,n).at n=15A005994
- a(n) = (n^3 + 2*n)/3.at n=18A006527
- Left diagonal of partition triangle A047812.at n=23A007042
- McKay-Thompson series of class 7A for Monster.at n=5A007264
- Number of strict first-order maximal independent sets in cycle graph.at n=26A007391
- a(n) = n*(a(n-1) + 1), a(0) = 0.at n=6A007526
- Coordination sequence T3 for Zeolite Code MEI.at n=32A008148
- Coordination sequence T2 for Zeolite Code ZON.at n=31A009920
- Spontaneous magnetization coefficients for square lattice spin 2 Ising model.at n=43A010103
- Numbers n such that phi(n) * sigma(n) + 9 is a perfect square.at n=25A015728
- Even 9-gonal (or enneagonal) numbers.at n=12A028992
- McKay-Thompson series of class 7A for the Monster group with a(0) = 10.at n=5A030183
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 28.at n=23A031526
- Number of binary [ n,4 ] codes without 0 columns.at n=12A034345
- a(n) = C(n+2,3) + 2*C(n,2) + 2*(n-2).at n=19A034857
- Number of partitions of n such that cn(0,5) = cn(1,5) <= cn(3,5) <= cn(2,5) = cn(4,5).at n=58A036864
- Molien series for 3-D group X1.at n=14A037240
- Sum of the next n members of the list of twin primes.at n=7A038345