8140
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 19152
- Proper Divisor Sum (Aliquot Sum)
- 11012
- 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
- 2880
- Möbius Function
- 0
- Radical
- 4070
- Omega Function (Ω)
- 5
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 158
- 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
- a(n) = (d(n)-r(n))/2, where d = A026037 and r is the periodic sequence with fundamental period (1,0,0,1).at n=34A026038
- Sum{T(k,k-1)}, k = 1,2,...,n, where T is the array in A026148.at n=9A026163
- Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 12 (most significant digit on right).at n=13A029505
- "DHK[ 5 ]" (bracelet, identity, unlabeled, 5 parts) transform of 1,1,1,1,...at n=32A032246
- Numbers k such that 211*2^k+1 is prime.at n=9A032482
- Four times pentagonal numbers: a(n) = 2*n*(3*n-1).at n=37A033579
- a(n) = (nextprime(4^n) - nextprime(2^n))/2.at n=7A037131
- Numbers whose base-4 representation contains exactly two 0's and four 3's.at n=23A045075
- Numbers whose base-5 representation contains exactly three 0's and two 3's.at n=21A045201
- Numbers n such that 59*2^n-1 is prime.at n=9A050555
- Numbers k such that k | sigma_6(k) + phi(k)^6.at n=12A055700
- Number of conics which pass through 3 points and are bitangent to a general curve of order n.at n=11A060783
- Number of (unordered) ways of making change for n cents using coins of 1/2, 1, 2, 3, 5, 10, 20, 25, 50, 100 cents (all historical U.S.A. coinage denominations up to 100 cents).at n=38A067997
- Numbers k such that phi(k) = bigomega(k)*tau(k)^2.at n=16A068540
- Expansion of 2*x*(1+x)*(1-2*x)/((1-x)^2*(1-2*x-x^2)).at n=10A133953
- G.f.: A(x) = exp( Sum_{n>=1} A162415(n)^2*x^n/n ) where A162415 is defined by: Sum_{n>=0} x^(2^n-1) = exp( Sum_{n>=1} A162415(n)*x^n/n ).at n=12A162416
- Let f(m) = number of steps needed to reach a Harshad number when the map k->A062028(l) is iterated starting at m; a(n) = smallest m such that f(m) = n.at n=97A181664
- Number of arrays of 2n nondecreasing integers in -3..3 with sum zero and equal numbers greater than zero and less than zero.at n=18A203286
- Array: row n shows the coefficients of the characteristic polynomial of the n-th principal submatrix of min(i(i+1)/2, j(j+1)/2) (A106255).at n=31A204024
- Number of (n+2)X4 0..3 arrays with every 3X3 subblock having three equal elements in a row horizontally, vertically, diagonally or antidiagonally exactly three ways, and new values 0..3 introduced in row major order.at n=6A204636