15786
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 34242
- Proper Divisor Sum (Aliquot Sum)
- 18456
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5256
- Möbius Function
- 0
- Radical
- 5262
- Omega Function (Ω)
- 4
- 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
- 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
- Egyptian fraction for 1/e.at n=2A006526
- Number of asymmetric (identity) trees with n nodes and 4 leaves.at n=37A055335
- a(1)=1; a(n+1) is the smallest integer such that 1/a(n+1) = 0.0...00a(n)xxxxx...at n=8A069750
- Kekulé numbers for certain benzenoids.at n=4A110693
- Even Padovan numbers divided by 2.at n=18A135619
- a(n) = ceiling(A000931(n)/2).at n=39A173692
- Number of n X 2 arrays of the minimum value of corresponding elements and their horizontal, vertical or diagonal neighbors in a random, but sorted with lexicographically nondecreasing rows and nonincreasing columns, 0..2 n X 2 array.at n=21A219810
- 27-gonal numbers: a(n) = n*(25*n-23)/2.at n=36A255186
- Partial sums of A256970.at n=33A256971
- Number of multigraphs on 4 unlabeled nodes with n edges where the edges can be of two colors.at n=10A261174
- Number of permutations p of [n] such that |p(i) - p(i-1)| is in {1,3} for all i from 2 to n.at n=19A302118
- a(n) is the smallest n-gonal number whose sum of digits is n.at n=24A359003