2211
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 6
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 3264
- Proper Divisor Sum (Aliquot Sum)
- 1053
- 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
- 1320
- Möbius Function
- -1
- Radical
- 2211
- Omega Function (Ω)
- 3
- 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
- yes
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 94
- 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
- Numbers k such that 39*2^k + 1 is prime.at n=28A002269
- Doubly triangular numbers: a(n) = n*(n+1)*(n^2+n+2)/8.at n=11A002817
- a(n) = n*(5*n^2 - 2)/3.at n=11A004466
- Number of graphs on n nodes with 3 cliques.at n=13A005289
- Coefficients of period polynomials.at n=17A006308
- Number of strict 5th-order maximal independent sets in cycle graph.at n=43A007393
- Numbers that contain only 1's and 2's. Nonempty binary strings of length n in lexicographic order.at n=26A007931
- Coordination sequence T3 for Zeolite Code AEL.at n=31A008006
- Coordination sequence T2 for Zeolite Code NES.at n=30A008206
- a(n) = p*(p-1)/2 for p = prime(n).at n=18A008837
- Coordination sequence T1 for Zeolite Code -WEN.at n=34A009862
- Coordination sequence T1 for Zeolite Code VSV.at n=30A009914
- a(0) = 1, a(n) = n^2 + 2 for n > 0.at n=47A010000
- Least d such that period of continued fraction for sqrt(d) contains n (n^2+2 if n odd, (n/2)^2+1 if n even).at n=46A013945
- Second hexagonal numbers: a(n) = n*(2*n + 1).at n=33A014105
- Representation of n in base of Catalan numbers (a classic greedy version).at n=41A014418
- Odd triangular numbers.at n=33A014493
- Binomial coefficients C(n,65).at n=2A017729
- Binomial coefficients C(67,n).at n=2A017783
- Expansion of g.f. 1/(1 - x^7 - x^8 - x^9 - x^10 - x^11).at n=54A017860