5565
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
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 10368
- Proper Divisor Sum (Aliquot Sum)
- 4803
- 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
- 2496
- Möbius Function
- 1
- Radical
- 5565
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
Special
- Factorial
- no
- Catalan Number
- no
- Bell Number
- no
- Motzkin Number
- no
- Primorial
- no
Figurate Numbers
- Fibonacci Number
- no
- Triangular Number
- yes
- Perfect Square
- no
- Perfect Cube
- no
- Pentagonal Number
- no
- Hexagonal Number
- yes
- 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
- 116
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- no
- Odd
- yes
Appears in sequences
- Doubly triangular numbers: a(n) = n*(n+1)*(n^2+n+2)/8.at n=14A002817
- a(n) = n*(n + 1)*(n^2 - 3*n + 5)/6.at n=14A006484
- Generalized Lucas numbers.at n=11A006493
- Coordination sequence T8 for Zeolite Code EUO.at n=46A008103
- Coordination sequence for sigma-CrFe, Position Xd.at n=19A009959
- Expansion of e.g.f.: cosh(log(x+1)-arcsin(x))=1+3/4!*x^4-10/5!*x^5+100/6!*x^6-525/7!*x^7...at n=8A013231
- a(n) = (2*n+1)*(4*n+1).at n=26A014634
- Cycle class sequence c(2n) (the number of true cycles of length 2n in which a certain node is included) for zeolite GME = Gmelinite (Na2,Ca)4 [ Al8Si16O48 ] . 24 H2O.at n=5A019018
- Pseudoprimes to base 13.at n=21A020141
- Pseudoprimes to base 22.at n=30A020150
- Pseudoprimes to base 29.at n=35A020157
- Pseudoprimes to base 34.at n=40A020162
- Pseudoprimes to base 41.at n=38A020169
- Pseudoprimes to base 43.at n=47A020171
- Pseudoprimes to base 62.at n=38A020190
- Pseudoprimes to base 71.at n=32A020199
- Pseudoprimes to base 83.at n=42A020211
- Pseudoprimes to base 92.at n=41A020220
- a(n) = least m such that if r and s in {1/2, 1/4, 1/6, ..., 1/(2*n)} satisfy r < s, then r < k/m < (k+3)/m < s for some integer k.at n=27A024845
- Expansion of 1/((1-2x)(1-5x)(1-8x)(1-10x)).at n=3A025998