6831
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
- 3
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 11520
- Proper Divisor Sum (Aliquot Sum)
- 4689
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3960
- Möbius Function
- 0
- Radical
- 759
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 44
- 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
- no
- Odd
- yes
Appears in sequences
- Expansion of 1/((1-2x)(1-7x)(1-8x)(1-10x)).at n=3A028006
- Number of partitions in parts not of the form 15k, 15k+1 or 15k-1. Also number of partitions with no part of size 1 and differences between parts at distance 6 are greater than 1.at n=41A035955
- Sum of the lengths of the cycle types of the permutation created by length sorting on the partitions of n.at n=30A036056
- Numbers whose base-4 representation contains exactly four 2's and two 3's.at n=15A045155
- Partial sums of A051797.at n=8A051878
- Numbers k such that k! is divisible by the square of (f+d)!^2 for d = 0, 1 and 2 (and possibly larger d), where f = floor(k/2).at n=29A056068
- a(1) = 3; a(n) is smallest number > a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.at n=42A074339
- a(1) = 6; a(n) is smallest number > a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.at n=47A074342
- Symmetric square table of coefficients, read by antidiagonals, where T(n,k) is the coefficient of x^n*y^k in f(x,y) that satisfies f(x,y) = (1-xy)/[(1-x)(1-y)] + xy*f(x,y)^3.at n=74A086626
- Symmetric square table of coefficients, read by antidiagonals, where T(n,k) is the coefficient of x^n*y^k in f(x,y) that satisfies f(x,y) = (1-xy)/[(1-x)(1-y)] + xy*f(x,y)^3.at n=69A086626
- Numbers k such that k^2 = x^3 + y^4 with positive integers x, y.at n=21A087209
- Molien series for symmetrized weight enumerators of self-dual codes over GF(4) + GF(4)u with u^2 = 0.at n=34A092549
- Number of partitions of n in which no parts are multiples of 25.at n=31A092885
- Structured truncated octahedral numbers.at n=10A100155
- Powers of e^(1/e) rounded up.at n=24A107586
- Shadow of sqrt(2).at n=41A110557
- a(1) = a(2) = 1. For n >=3, a(n) = the a(n-2)th integer, among those positive integers which are missing from the first (m-1) terms of the sequence, below a(n-1) if such a positive integer exists. Otherwise, a(n) = the a(n-2)th integer, among those positive integers which are missing from the first (m-1) terms of the sequence, above a(n-1).at n=31A118627
- A polynomial of matrices is used to make a triangular sequence. The upper triangular antidiagonal Steinbach matrices are summed over their characteristic polynomial triangular sequences to give a new sequence of matrices: the characteristic polynomials of these new summed matrices are, then, used to make up this triangular sequence.at n=17A123951
- Odd interprimes divisible by 11.at n=32A126230
- n such that floor(sqrt(10^(2*n-1))) is (probably) prime.at n=8A136583