9228
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
- 4
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 21560
- Proper Divisor Sum (Aliquot Sum)
- 12332
- 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
- 3072
- Möbius Function
- 0
- Radical
- 4614
- Omega Function (Ω)
- 4
- 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
- 153
- 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
- Low temperature series for spin-1/2 Ising partition function on 2D square lattice.at n=10A002890
- Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 16.at n=11A031694
- Number of partitions of n with equal nonzero number of parts congruent to each of 0, 3 and 4 (mod 5).at n=52A035587
- Number of resistance values that can be constructed using exactly n 1-ohm resistors in series or parallel but not with fewer resistors.at n=11A051389
- G.f.: A(x) = exp(sum(n>=1, A084250(n)*x^n/n)), where A084250 lists the least distinct positive integers that allow A(x) to be an integer power series.at n=33A084251
- Number of partitions of n with no part larger than n/2. Also partitions of n into n/2 or fewer parts.at n=33A110618
- (1/8)*number of lattice points with odd indices in a cubic lattice inside a sphere around the origin with radius 2*n.at n=25A120884
- a(n) = n!*b(n) where b(n) = (b(n-2) + b(n-3))/(n*(n-1)), b(0) = b(1) = b(2) = 1.at n=14A123024
- Set m = 0, n = 1. Find smallest k >= 2 such that pi(k) = (k-pi(k)) - (m-pi(m)); set a(n) = pi(k), m = k, n = n+1. Repeat.at n=45A131872
- a(n) = 256*n^2 + 2*n.at n=5A158230
- a(n) = 144*n^2 + 12.at n=8A158546
- Number of strings of numbers x(i=1..5) in 0..n with sum i^4*x(i) equal to 625*n.at n=47A184351
- Number of partitions of n in which all parts are less than n/2.at n=33A210249
- Nonsquare k such that the minimal (in y) solution 0 < y < x of x^2 - k*y^2 = 1 has x-y square.at n=45A225946
- Duplicate of A210249.at n=32A233771
- Numbers k such that Bernoulli number B_k has denominator 2730.at n=35A249134
- Numbers k such that A084937(3k) > A084937(3k+1).at n=20A249689
- Number of (n+1)X(2+1) 0..1 arrays with every 2X2 subblock sum nondecreasing horizontally, vertically and antidiagonally ne-to-sw.at n=6A253320
- T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with every 2X2 subblock sum nondecreasing horizontally, vertically and antidiagonally ne-to-sw.at n=34A253326
- Number of (7+1)X(n+1) 0..1 arrays with every 2X2 subblock sum nondecreasing horizontally, vertically and antidiagonally ne-to-sw.at n=1A253332