2856
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
- 32
- Divisor Sum
- 8640
- Proper Divisor Sum (Aliquot Sum)
- 5784
- 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
- 768
- Möbius Function
- 0
- Radical
- 714
- Omega Function (Ω)
- 6
- Little Omega Function (ω)
- 4
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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 35
- 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
- Number of stacks, or arrangements of n pennies in contiguous rows, each touching 2 in row below.at n=25A001524
- The coding-theoretic function A(n,4,4).at n=38A001843
- Hexagonal pyramidal numbers, or greengrocer's numbers.at n=16A002412
- Expansion of 1/((1-x)^4*(1+x)).at n=30A002623
- Representation degeneracies for Neveu-Schwarz strings.at n=20A005295
- Coordination sequence T1 for Zeolite Code APC.at n=37A008032
- Coordination sequence T5 for Zeolite Code BOG.at n=38A008053
- Coordination sequence T2 for Zeolite Code LAU.at n=38A008125
- Coordination sequence T4 for Zeolite Code LTN.at n=37A008143
- Coordination sequence T7 for Zeolite Code NES.at n=34A008211
- a(n) = floor(n*(n-1)*(n-2)/15).at n=36A011897
- a(n) = floor(n(n-1)(n-2)(n-3)/20).at n=17A011930
- sin(arctan(x)*sin(x))=2/2!*x^2-12/4!*x^4+70/6!*x^6+2856/8!*x^8...at n=3A012421
- arcsinh(arctan(x)*sin(x))=2/2!*x^2-12/4!*x^4+70/6!*x^6+2856/8!*x^8...at n=3A012426
- Even hexagonal pyramidal numbers.at n=7A015226
- a(n) is the concatenation of n and 2n.at n=27A019550
- a(n) = n*(13*n - 1)/2.at n=21A022270
- Positive integers which apparently never result in a palindrome under repeated applications of the function A056964(x) = x + (x with digits reversed).at n=35A023108
- a(n) = 1*(n) + 2*(n-1) + 3*(n-2) + ... + (n+1-k)*k, where k = floor((n+1)/2).at n=30A023855
- Least modulus >= 3 having maximum run of n consecutive non-residues.at n=50A025034