2124
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 9
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 18
- Divisor Sum
- 5460
- Proper Divisor Sum (Aliquot Sum)
- 3336
- 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
- 696
- Möbius Function
- 0
- Radical
- 354
- Omega Function (Ω)
- 5
- 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
- 125
- 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
- Number of bicentered hydrocarbons with n atoms.at n=15A000200
- Squares written in base 5.at n=17A001740
- Squares written in base 6.at n=22A001741
- Number of partitions of 3n-1 into n nonnegative integers each no more than 6.at n=16A001978
- Number of nonequivalent dissections of an n-gon into n-4 polygons by nonintersecting diagonals rooted at a cell up to rotation and reflection.at n=5A003448
- Positions of remoteness 5 in Beans-Don't-Talk.at n=42A005697
- Coordination sequence T3 for Zeolite Code AFR.at n=35A008021
- Coordination sequence T2 for Zeolite Code iRON.at n=32A009882
- Coordination sequence T2 for Zeolite Code WEI.at n=32A009918
- Base-5 Armstrong or narcissistic numbers, written in base 5.at n=8A010345
- Aliquot sequence starting at 564.at n=3A014361
- Number of lines through exactly 10 points of an n X n grid of points.at n=51A018817
- Coordination sequence T1 for Zeolite Code SAO.at n=36A019571
- a(n) = Sum_{k=1..n} k*floor( prime(k)/k ).at n=35A024927
- Coordination sequence T2 for Zeolite Code CGS.at n=34A027366
- Numbers with 18 divisors.at n=34A030636
- Numbers whose base-5 representation has 3 fewer 0's than 4's.at n=37A031476
- 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 22.at n=35A031520
- Number of ways to partition n elements into pie slices of different odd sizes.at n=50A032154
- Concatenation of n and n + 3.at n=20A032608