8522
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 12786
- Proper Divisor Sum (Aliquot Sum)
- 4264
- 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
- 4260
- Möbius Function
- 1
- Radical
- 8522
- 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
- yes
- 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
- yes
- Odd
- no
Appears in sequences
- Numbers k such that the continued fraction for sqrt(k) has period 19.at n=43A020358
- Discriminants of real quadratic fields with class number 2 and related continued fraction period length of 19.at n=5A051984
- Sum of smallest parts of all partitions of n into distinct parts.at n=49A092265
- Sums of three consecutive heptagonal numbers.at n=33A129111
- 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, -1), (1, -1, 1), (1, 1, 0)}.at n=8A149012
- G.f.: A(x) = exp( Sum_{n>=1} sigma(n)*|A002129(n)|*x^n/n ).at n=14A162420
- Positions of zeros in A165582.at n=36A165583
- Number of 9-step S, E, and NW-moving king's tours on an n X n board summed over all starting positions.at n=5A187514
- Let K be a local ring with a principal maximal ideal J of nilpotent degree 4 with |K/J|>2; a(n) = number of D-invariant ideals in the ring R_n(K,J).at n=4A221704
- a(n) = Sum_{i=0..n} digsum_5(i)^4, where digsum_5(i) = A053824(i).at n=20A231671
- Numbers n such that the decimal expansions of both n and n^2 have 2 as smallest digit and 8 as largest digit.at n=26A257368
- G.f.: 1/((1-t^6)*(1-t)*(1-t^3)*(1-t^5)*(1-t^7)*(1-t^9)*(1-t^11)).at n=65A266746
- Maximal term of TRIP-Stern sequence of level n corresponding to permutation triple (e,13,23).at n=26A271486
- Numbers k such that A338338(k) is a prime p that ends a run of three terms in A338338 that are divisible by p.at n=21A338344
- Number of compositions (ordered partitions) of n into distinct parts such that the smallest part is equal to the number of parts.at n=49A339446
- Numbers k such that phi(k) = phi(sigma(k)) and A003958(k) = A003958(sigma(k)).at n=52A353635
- G.f. satisfies A(x) = 1 + x*A(x)^3 / (1 + x*A(x)^4).at n=9A365223