15868
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 27776
- Proper Divisor Sum (Aliquot Sum)
- 11908
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7932
- Möbius Function
- 0
- Radical
- 7934
- Omega Function (Ω)
- 3
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 53
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- Let (u1,u2) be successive untouchable numbers such that phi(u1) = phi(u2); sequence gives values of u2.at n=34A048190
- Numbers n such that 107*2^n-1 is prime.at n=19A050579
- Number of binary arrays indicating the locations of trailing edge maxima of a random length-n 0..7 array extended with zeros and convolved with 1,2,2,1.at n=20A222110
- a(n) = 9*n^3/2 - 21*n^2/2 + 8*n - 4.at n=14A232495
- Number of partitions of n such that (least part) > (multiplicity of least part).at n=52A240176
- Number of length 6 0..n arrays least squares fitting to a zero slope straight line, with a single point taken as having zero slope.at n=8A245136
- Numbers of the form 5^x + y^5 with x, y >= 0.at n=44A250546
- Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 374", based on the 5-celled von Neumann neighborhood.at n=13A281524
- Numbers of the form a^5 + b^6, with integers a, b > 0.at n=26A303375
- Number T(n,k) of subsets of [n] with k binary carry-connected components; triangle T(n,k), n >= 0, 0 <= k <= A029837(n+1), read by rows.at n=56A306297
- Expansion of (1/(1 - x)) * Product_{k>=1} 1/(1 - k*x^k/(1 - x)^k).at n=9A318127
- a(n) is the number of edges formed by n-secting the angles of a square.at n=42A335527
- G.f. satisfies A(x) = 1/(1 - 5*x) - x*A(x)^3.at n=7A364647