8551
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 9072
- Proper Divisor Sum (Aliquot Sum)
- 521
- 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
- 8032
- Möbius Function
- 1
- Radical
- 8551
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- 78
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- no
- Odd
- yes
Appears in sequences
- Nonsquare values of m in the discriminant D = 4*m leading to a new maximum of the L-function of the Dirichlet series L(1) = Sum_{k>0} Kronecker(D,k)/k.at n=31A003421
- Numbers k such that the continued fraction for sqrt(k) has period 100.at n=13A020439
- 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 91.at n=24A031589
- Digitally balanced numbers in both bases 2 and 3.at n=12A049361
- Differences between numbers k such that k and k+1 have the same sum of divisors.at n=22A054001
- a(n) = 4*n^2 + 10*n + 1.at n=45A082112
- Triangle related to Bell numbers; T(n,k) read by rows, n>=0, 0<=k<=n: T(n,k) = k*T(n-1,k) + Sum(0<=j, T(n-1,k-1+j)); T(0,0)=1, T(0,k)=0 if k>0.at n=40A086211
- a(n) = (27*n^2 + 9*n + 2)/2.at n=25A093485
- Number of hierarchical orderings with at least 2 elements on each level for n unlabeled elements. Unlabeled analog of A097236.at n=18A109509
- Expansion of 1 + Sum_{k>0} x^k^2/((1-x)(1-x^2)...(1-x^(2k))).at n=48A122129
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, -1), (-1, 0, 1), (0, 1, 0), (1, -1, 1), (1, 0, -1)}.at n=9A148382
- a(n) = 225*n + 1.at n=37A158229
- a(n) = 38*n^2 + 1.at n=15A158593
- Semiprime centered triangular numbers.at n=29A184481
- G.f. satisfies A(x) = (1 + x*A(x)) * (1 + x*A(x)^4).at n=5A215623
- Number of (n+3) X 6 0..2 matrices with each 4 X 4 subblock idempotent.at n=7A224723
- Odd integers k such that for every m >= 1 the numbers k*4^m - 1 have at least three prime factors, not necessarily distinct, and k*4^m - 1 has at least two-element covering set.at n=12A233552
- Expansion of g.f. (1-2*x+51*x^2)/(1-x)^3.at n=19A257352
- Alternating sum of centered 25-gonal numbers.at n=36A270693
- a(n) = (4*n^3 - 6*n^2 + 20*n + 3)/3.at n=19A322597