2223
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 9
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- yes
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 3640
- Proper Divisor Sum (Aliquot Sum)
- 1417
- 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
- 1296
- Möbius Function
- 0
- Radical
- 741
- 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
- 182
- 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
- no
- Odd
- yes
Appears in sequences
- Number of centered hydrocarbons with n atoms.at n=15A000022
- Maximal number of pairwise relatively prime polynomials of degree n over GF(2).at n=15A001115
- a(n) = n concatenated with n + 1.at n=21A001704
- The coding-theoretic function A(n,4,4).at n=35A001843
- Number of series-reduced planted trees with n+9 nodes and 4 internal nodes.at n=16A001860
- a(n) = n*(n + 1)*(n^2 - 3*n + 6)/8.at n=11A004255
- Maxima of the rows of the triangle A259095.at n=33A005577
- In the '3x+1' problem, these values for the starting value set new records for number of steps to reach 1.at n=21A006877
- Kaprekar numbers: positive numbers n such that n = q+r and n^2 = q*10^m+r, for some m >= 1, q >= 0 and 0 <= r < 10^m, with n != 10^a, a >= 1.at n=8A006886
- a(n) = n OR n^2 (applied to binary expansions).at n=46A007745
- Coordination sequence T2 for Zeolite Code MEP.at n=28A008158
- Coordination sequence T2 for Zeolite Code MFI.at n=30A008165
- Coordination sequence T4 for Zeolite Code MFI.at n=30A008167
- Number of partitions of n into parts >= 4.at n=48A008484
- Coordination sequence T3 for Zeolite Code ZON.at n=33A009921
- Numbers k that divide s(k), where s(1)=1, s(j)=9*s(j-1)+j.at n=19A014857
- a(n) = 3*a(n-1) + 10*a(n-2).at n=6A015528
- Number of triples of different integers from [ 2,n ] with no global factor.at n=25A015618
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly five 1's.at n=20A020441
- Denominator of n*(n-3)*(3*n^2 - 6*n + 2)/(3*(n-1)*(n-2)).at n=37A023418