9006
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 19200
- Proper Divisor Sum (Aliquot Sum)
- 10194
- 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
- 2808
- Möbius Function
- 1
- Radical
- 9006
- 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
- 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
- 39
- 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
- yes
- Odd
- no
Appears in sequences
- Strobogrammatic numbers: the same upside down.at n=34A000787
- Numbers that are the sum of 8 positive 7th powers.at n=32A003375
- Numerators of continued fraction convergents to sqrt(536).at n=6A042024
- a(n) = Sum_{k=0..n} C(n,k)*Stirling2(n,k)^2.at n=5A047798
- Convolution of L(n+1) := A000204(n+1) (Lucas), n>=0, with L(n+3), n>=0.at n=10A067981
- Numbers that look the same when rotated by 180 degrees, using only digits 0, 6 and 9.at n=8A111065
- Numbers that look the same when printed upside down.at n=19A111156
- Numbers n such that every digit occurs at least once in n^3.at n=37A119735
- a(1) = 1; a(n) = max{ 5*a(k) + a(n-k) | 1 <= k <= n/2 } for n > 1.at n=41A130667
- a(n) = 25*n^2 - n.at n=18A157514
- a(n) = 361*n^2 - 19.at n=4A158595
- Number of different deltoids (including squares) whose vertices are on an n X n grid.at n=29A159944
- Smallest sequence which lists the position of digits "8" in the sequence.at n=39A167450
- Numbers that are the same upside down (using only digits 0, 1, 6 and 9).at n=19A169731
- Triangle of coefficients of polynomials v(n,x) jointly generated with A209575; see the Formula section.at n=53A209576
- Ending letter of a(n) equals starting letter of a(n+1), when spelled out in German; always choose the smallest possible number not yet used and not ending the sequence.at n=52A228442
- Numbers equidistant from twin prime pairs that are also equidistant from numbers equidistant from twin prime pairs.at n=14A260517
- Number of integers in n-th generation of tree T(1/2) defined in Comments.at n=25A274142
- Strobogrammatic nonpalindromic numbers.at n=17A287092
- Expansion of Product_{k>0} theta_3(q^(2*k))/theta_3(q^(2*k-1)), where theta_3() is the Jacobi theta function.at n=14A321027