9969
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 33
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 5
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 13296
- Proper Divisor Sum (Aliquot Sum)
- 3327
- 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
- 6644
- Möbius Function
- 1
- Radical
- 9969
- 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
- 91
- 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
- no
- Odd
- yes
Appears in sequences
- 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 66.at n=32A031564
- Denominators of continued fraction convergents to sqrt(239).at n=7A041447
- Denominators of continued fraction convergents to sqrt(394).at n=11A041749
- Denominators of continued fraction convergents to sqrt(956).at n=9A042851
- Numbers having three 9's in base 10.at n=24A043527
- Numbers whose base-5 representation contains exactly three 3's and two 4's.at n=33A045306
- Expansion of (1+6*x)/((1-2*x-x^2)*(1-x)^2).at n=8A051959
- Numbers k > 1 such that, in base 4, k and k^2 contain the same digits in the same proportion.at n=38A061658
- Harmonic mean of digits is 8.at n=6A062185
- Near-repdigit semiprimes with 9 as repeated digit.at n=21A105990
- Semiprimes with semiprime digits (digits 4, 6, 9 only).at n=32A107342
- Expansion of 1/(1+x*(2-x)*c(-2*x)), c(x) the g.f. of A000108.at n=6A114194
- Starting numbers for which the RATS sequence has eventual period 14.at n=33A114615
- Numbers k such that 2^(2*k - 1) - 1 is prime.at n=22A138576
- Numbers with rounded up arithmetic mean of digits = 9.at n=39A178369
- Number of simple squared rectangles of order n up to symmetry.at n=7A220167
- Odd numbers k such that phi(k) and cototient(k) have the same prime signature.at n=12A280927
- Numbers with digits 6 and 9 only.at n=27A284636
- Number of Dyck paths of semilength n such that no positive level has fewer than four peaks.at n=15A288680
- Triangle T(n,k) read by rows: the number of semigroups of orientation-preserving partial transformations on n element with right waist k.at n=27A289714