228
domain: N
Properties
Digital Properties
- Digit Count
- 3
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 560
- Proper Divisor Sum (Aliquot Sum)
- 332
- 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
- 72
- Möbius Function
- 0
- Radical
- 114
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 34
- Smith 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
Names
- German
- zweihundertachtundzwanzig· ordinal: zweihundertachtundzwanzigste
- English
- two hundred twenty-eight· ordinal: two hundred twenty-eighth
- Spanish
- doscientos veintiocho· ordinal: 228º
- French
- deux cent vingt-huit· ordinal: deux cent vingt-huitième
- Italian
- duecentoventotto· ordinal: 228º
- Latin
- ducenti viginti octo· ordinal: 228.
- Portuguese
- duzentos e vinte e oito· ordinal: 228º
Appears in sequences
- Numbers k such that k^4 + 1 is prime.at n=33A000068
- Erroneous version of A003713.at n=5A000154
- Number of inequivalent ways of dissecting a regular (n+2)-gon into n triangles by n-1 non-intersecting diagonals under rotations and reflections; also the number of (unlabeled) maximal outerplanar graphs on n+2 vertices.at n=8A000207
- Number of partitions into non-integral powers.at n=9A000327
- Expansion of x^3*(5-2*x)*(1-x^3)/(1-x)^4.at n=6A000338
- Number of steps to reach 1 in sequence A000546.at n=55A000547
- Numbers that are divisible by at least three different primes.at n=35A000977
- Moran numbers: k such that k/(sum of digits of k) is prime.at n=22A001101
- A self-generating sequence: a(1)=1, a(2)=2, a(n+1) chosen so that a(n+1)-a(n-1) is the first number not obtainable as a(j)-a(i) for 1<=i<j<=n.at n=19A001149
- a(n) is the solution to the postage stamp problem with n denominations and 4 stamps.at n=7A001214
- Numbers of form m*k with m+1 <= k <= 2m-1.at n=64A001284
- Partial sums of A001462; also a(n) is the last occurrence of n in A001462.at n=33A001463
- Winning moves in Fibonacci nim.at n=39A001581
- Fibonacci entry points: a(n) = smallest m > 0 such that the n-th prime divides Fibonacci(m).at n=48A001602
- The coding-theoretic function A(n,4,3).at n=37A001839
- The coding-theoretic function A(n,4,4).at n=15A001843
- Beatty sequence of (5+sqrt(13))/2.at n=52A001956
- Numbers congruent to {2, 4, 8, 16} (mod 20).at n=46A002081
- Numbers x such that x^2 + y^2 = p^2 = A002144(n)^2, x < y.at n=36A002366
- Period of decimal expansion of 1/(n-th prime) (0 by convention for the primes 2 and 5).at n=49A002371