9087
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 13104
- Proper Divisor Sum (Aliquot Sum)
- 4017
- 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
- 5568
- Möbius Function
- -1
- Radical
- 9087
- 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
- yes
- 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
- 184
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) = Sum_{k=1..n} k*phi(k).at n=34A011755
- Expansion of 1/((1-x)^3*(1-x^3)^2).at n=33A011779
- Odd pentagonal numbers.at n=39A014632
- a(n) = least m such that if r and s in {1/1, 1/4, 1/7, ..., 1/(3n-2)} satisfy r < s, then r < k/m < (k+1)/m < s for some integer k.at n=42A024836
- a(n) = least m such that if r and s in {1/1, 1/3, 1/5, ..., 1/(2n-1)} satisfy r < s, then r < k/m < (k+2)/m < s for some integer k.at n=41A024841
- Number of plane regions after drawing (in general position) a convex n-gon and all its diagonals.at n=21A027927
- Number of partitions satisfying cn(2,5) + cn(3,5) <= cn(0,5) + cn(1,5) and cn(2,5) + cn(3,5) <= cn(0,5) + cn(4,5).at n=38A039865
- Denominators of continued fraction convergents to sqrt(423).at n=8A041805
- Pentagonal numbers with even index.at n=39A049452
- a(n) = T(n,n-4), array T as in A055801.at n=43A055804
- Least k for the Theodorus spiral to complete n revolutions.at n=29A072895
- Bases of the n-th powers in A090900.at n=17A110042
- Starting numbers for which the RATS sequence has eventual period 14.at n=21A114615
- Pentagonal numbers for which the product of the digits is also a pentagonal number.at n=32A117710
- Pentagonal numbers that are the sum of a nonzero pentagonal number and a nonzero square in at least one way.at n=28A134938
- A sequence of asymptotic density zeta(8) - 1, where zeta is the Riemann zeta function.at n=37A143034
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 1, -1), (0, 0, 1), (0, 1, 1), (1, 0, 0)}.at n=7A151043
- a(n) = Sum_{k=1..n} lcm(k,k')/gcd(k,k'), where n' is arithmetic derivative of n.at n=47A190120
- Expansion of series reversion of x/(1 + x + 2*x^4).at n=12A190590
- Number of (w,x,y,z) with all terms in {1,...,n} and w+x=|x-y|+|y-z|.at n=26A212676