3840
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 36
- Divisor Sum
- 12264
- Proper Divisor Sum (Aliquot Sum)
- 8424
- 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
- 1024
- Möbius Function
- 0
- Radical
- 30
- Omega Function (Ω)
- 10
- 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
- 25
- 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
- yes
- Carmichael Number
- no
Classification
- Even
- yes
- Odd
- no
Appears in sequences
- Double factorial of even numbers: (2n)!! = 2^n*n!.at n=5A000165
- Jordan-Polya numbers: products of factorial numbers A000142.at n=44A001013
- Double-bitters: only even length runs in binary expansion.at n=48A001196
- Sorted list of orders of Weyl groups of types A_n, B_n, D_n, E_n, F_4, G_2.at n=14A001217
- Hexanacci numbers: a(n+1) = a(n)+...+a(n-5) with a(0)=...=a(4)=0, a(5)=1.at n=18A001592
- Expansion of (1+x^2) / ( (1-x)^2 * (1-x^3)^2 ).at n=44A006501
- Double factorials n!!: a(n) = n*a(n-2) for n > 1, a(0) = a(1) = 1.at n=10A006882
- Coordination sequence T1 for Zeolite Code ANA.at n=40A008031
- Coordination sequence T1 for Zeolite Code DOH.at n=38A008078
- Coordination sequence T2 for Zeolite Code MOR.at n=40A008183
- Theta series of {D_6}^{+} lattice.at n=31A008434
- Expansion of e.g.f. cosh(log(1+tanh(x))).at n=9A009126
- Prefix (or Levenshtein) codes for natural numbers.at n=16A010097
- Denominators in the Taylor expansion exp(cosec(x)-cot(x))=1 + x/2 + x^2/8 + x^3/16 + 3*x^4/128 + 37*x^5/3840 + 59*x^6/15360 + ...at n=5A013516
- Triangle of coefficients in expansion of (1+4x)^n.at n=25A013611
- Theta series of lattice Kappa_7.at n=15A015236
- Numbers k such that phi(k) + 2 | sigma(k + 2).at n=16A015781
- Number of subsets of { 1, ..., n } containing an A.P. of length 8.at n=17A018793
- a(n) = 8^n - n^4.at n=4A024092
- Let c(k) denote the k-th composite number and p(k) the k-th prime number; then a(n) = Sum_{i=n*(n-1)/2+1 .. n*(n+1)/2} c(i) - Sum_{i=1..n} p(i).at n=18A024850