2206
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 10
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3312
- Proper Divisor Sum (Aliquot Sum)
- 1106
- 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
- 1102
- Möbius Function
- 1
- Radical
- 2206
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 45
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) = a(n-1) + a(n-2) + 1, with a(0) = 0 and a(1) = 2.at n=15A001610
- a(n) = floor(n*phi^16), where phi is the golden ratio, A001622.at n=1A004931
- a(n) = F(2n+1) + F(2n-1) - 1.at n=8A005592
- Number of cyclic binary n-bit strings with no alternating substring of length > 2.at n=15A007039
- Number of (marked) cyclic n-bit binary strings containing no runs of length > 2.at n=15A007040
- Number of self-complementary 2-colored bracelets (turnover necklaces) with 2n beads.at n=12A007148
- Coordination sequence T2 for Zeolite Code ATV.at n=30A008044
- Coordination sequence T3 for Zeolite Code MEI.at n=34A008148
- Coordination sequence T1 for Banalsite.at n=28A008249
- Coordination sequence T2 for Banalsite.at n=28A008250
- Coordination sequence T2 for Zeolite Code RUT.at n=31A009898
- Coordination sequence T5 for Zeolite Code RUT.at n=31A009901
- Coordination sequence for FeS2-Marcasite, Fe position.at n=23A009955
- a(n) = floor(phi^n), where phi = (1+sqrt(5))/2 is the golden ratio.at n=16A014217
- Numbers k such that the continued fraction for sqrt(k) has period 80.at n=2A020419
- a(n) is the position of square of n-th prime among the powers of primes (A000961).at n=32A024624
- Positions of squares among the powers of primes (A000961).at n=46A024626
- a(n) = least m such that if r and s in {1/1, 1/2, 1/3, ..., 1/n} satisfy r < s, then r < k/m < (k+4)/m < s for some integer k.at n=21A024846
- a(n) = Sum_{i=1..floor((n+2)/4)} a(2i-1)*a(n-2i+1), with a(1)=a(2)=1 and a(3)=2.at n=15A024945
- s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (Fibonacci numbers), t = A014306.at n=31A025087