2066
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3102
- Proper Divisor Sum (Aliquot Sum)
- 1036
- 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
- 1032
- Möbius Function
- 1
- Radical
- 2066
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 156
- 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
- Numbers k such that 15*2^k - 1 is prime.at n=25A002237
- a(n)=least number m such that m-a(n-1)<>a(j)-a(k) for all j,k less than m; a(1)=1, a(2)=3.at n=43A004979
- Number of protruded partitions of n with largest part at most 2.at n=13A005403
- 'Eban' numbers (the letter 'e' is banned!).at n=38A006933
- Number of distinct perforation patterns for deriving (v,b) = (n+3,n) punctured convolutional codes from (2,1).at n=5A007224
- Coordination sequence T11 for Zeolite Code MFI.at n=29A008163
- Coordination sequence T1 for Zeolite Code STI.at n=31A008234
- Coordination sequence T1 for Zeolite Code VFI.at n=35A008245
- Coordination sequence T2 for Zeolite Code RTE.at n=31A009891
- a(n) = floor( n*(n-1)*(n-2)/19 ).at n=35A011901
- Third differences of Bell numbers.at n=5A011966
- Aitken's array: triangle of numbers {a(n,k), n >= 0, 0 <= k <= n} read by rows, defined by a(0,0)=1, a(n,0) = a(n-1,n-1), a(n,k) = a(n,k-1) + a(n-1,k-1).at n=32A011971
- Sequence formed by reading rows of triangle defined in A011971.at n=25A011972
- Expansion of 1/((1-x)(1-5x)(1-10x)).at n=3A016237
- Pisot sequence P(7,11), a(0)=7, a(1)=11, a(n+1) is the nearest integer to a(n)^2/a(n-1). Agrees with A021014 only for n <= 20.at n=13A021013
- a(n)=a(n-1)+a(n-2)-a(n-4)+a(n-5).at n=13A021014
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (composite numbers), t = (F(2), F(3), F(4), ...).at n=9A025103
- a(n) = [ 3rd elementary symmetric function of {sqrt(k)} ], k = 1,2,...,n.at n=8A025194
- Positions of records in A030757.at n=40A030762
- 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 44.at n=9A031542