3686
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 5880
- Proper Divisor Sum (Aliquot Sum)
- 2194
- 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
- 1728
- Möbius Function
- -1
- Radical
- 3686
- 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
- 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
- 131
- 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
- Expansion of 1/((1-x)*(1-x-2*x^3)).at n=15A003479
- Coordination sequence T2 for Zeolite Code APC.at n=42A008033
- Coordination sequence T3 for Zeolite Code FER.at n=37A008108
- a(n) = (d(n)-r(n))/5, where d = A026040 and r is the periodic sequence with fundamental period (4,0,4,3,4).at n=35A026042
- n-th diagonal sum of right justified array T given by A027960.at n=16A027976
- 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 60.at n=6A031558
- Sort then Add, a(1)=17.at n=8A033899
- Numerators of continued fraction convergents to sqrt(185).at n=7A041342
- Coordination sequence T2 for Zeolite Code ISV.at n=42A047959
- Number of objects generated by the Combstruct grammar defined in the Maple program. See the link for the grammar specification.at n=8A052891
- Numbers n such that 1n1, 3n3, 7n7 and 9n9 are all primes.at n=8A059677
- Product of n-th prime number and n-th composite number.at n=24A067563
- Solution to the merit factor problem.at n=57A091386
- a(n) = (15*n^2 + 5*n + 2)/2.at n=21A093500
- Positive integers n such that n^10 + 1 is semiprime.at n=39A105078
- Cumulative sum of absolute values of coefficients of q^(2n) in the series expansion of Ramanujan's mock theta function f(q).at n=25A109471
- Triangle read by rows: T(n,k) is the number of Dyck paths of semilength n having k UUDD's starting at level 0; here U=(1,1), D=(1,-1) (0<=k<=floor(n/2)).at n=25A114486
- Number of Dyck paths of semilength n having no UUDD's starting at level 0.at n=9A114487
- Values of A083097(k) such that A083097(k) = A083097(k+1) - 1.at n=42A122485
- Product of the first n 5-almost primes (A014614), divided by product of the first n primes, rounded down.at n=2A122609