6546
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
- 8
- Divisor Sum
- 13104
- Proper Divisor Sum (Aliquot Sum)
- 6558
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 2180
- Möbius Function
- -1
- Radical
- 6546
- Omega Function (Ω)
- 3
- 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
- 137
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- yes
- 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
- Worst cases for Pierce expansions (numerators).at n=26A006537
- a(n) = a(n-1) + a(n-2) + a(n-3).at n=14A007486
- Number of words of length n (n >= 1) over a two-letter alphabet having a minimal period of size n-2.at n=14A019311
- n written in fractional base 7/6.at n=27A024643
- 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 80.at n=10A031578
- a(n) = n*(n^2 - 6*n + 11)/6.at n=36A050407
- a(n) = (11*n^2 - 11*n + 2)/2.at n=34A069125
- a(0) = 2 and, for n >= 1, rewrite 0->100 in the binary expansion of n and append 10 to the right.at n=20A080310
- Numbers k such that phi(k) | sigma_18(k).at n=11A094470
- Let T(S,Q) be the sequence obtaining by starting with S and repeatedly reversing the digits and adding Q to get the next term. This is T(1016,5), the first S for which T(S,5) reaches a cycle of length 36.at n=17A118879
- Number of distinct values taken by the entropy for permutations of [1..n], where the entropy of a permutation pi is Sum_{k=1..n} (pi(k)-k)^2.at n=34A126972
- Triangle T(n,k): the coefficient of [x^k] of the series -(x-1)^(2*n+1) *Sum_{j>=0} (j+1)^n *binomial(j,n) * x^(j-n); columns 0<=k<n.at n=12A155163
- Polynomial triangle sequence of coefficients: p(x,n)=-((x - 1)^(2*n + 1)/x^n)*Sum[(k + 1)^n*Binomial[k, n]*x^k, {k, 0, Infinity}]. q(x,n)=(p(x,n)+x^n*p(1/x,n))/2.at n=13A155164
- a(n) = 9^n-2^n+1^n.at n=4A155600
- Number of integral solutions to the equation (x_1)^3 + ... + (x_n)^3 = (x_1 + ... + x_n)^2 with 1 <= x_1 <= ... <= x_n.at n=12A158649
- Second right hand column of the Beta triangle A160480.at n=15A160483
- Numbers x such that 0 < |x^7 - y^2| < x^(5/2) for some number y.at n=5A173348
- Sums of 3 consecutive semiprimes.at n=27A173968
- Sums of three consecutive numbers each of which is the product of two distinct primes and each of which has no exponent greater than one for either of its two prime factors.at n=25A173969
- Partial sums of floor(2^n/5).at n=13A178452