15942
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 31896
- Proper Divisor Sum (Aliquot Sum)
- 15954
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 5312
- Möbius Function
- -1
- Radical
- 15942
- 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
- 53
- 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
- Numbers k such that 225*2^k+1 is prime.at n=36A032489
- Number of partitions of n into parts not of the form 17k, 17k+5 or 17k-5. Also number of partitions with at most 4 parts of size 1 and differences between parts at distance 7 are greater than 1.at n=38A035966
- McKay-Thompson series of class 17A for the Monster simple group.at n=19A058530
- a(n)=floor{square((1*n^0+1*n^1+2*n^2+4*n^3)/(1*n^0+2*n^1+1*n^2))}.at n=32A086863
- Triangle read by rows: T(n,k) is number of hex trees with n edges and level of first leaf (in the preorder traversal) equal to k (1 <= k <= n).at n=37A126186
- McKay-Thompson series of class 17A for the Monster group with a(0) = 2.at n=19A152944
- Number of nX3 binary arrays without the pattern 0 1 0 diagonally, vertically, antidiagonally or horizontally.at n=5A188689
- Number of nX6 binary arrays without the pattern 0 1 0 diagonally, vertically, antidiagonally or horizontally.at n=2A188692
- T(n,k)=Number of nXk binary arrays without the pattern 0 1 0 diagonally, vertically, antidiagonally or horizontally.at n=30A188695
- T(n,k)=Number of nXk binary arrays without the pattern 0 1 0 diagonally, vertically, antidiagonally or horizontally.at n=33A188695
- Number of unlabeled connected simplicial complexes with n nodes.at n=6A261006
- Number of length-n 0..2 arrays with no repeated value differing from the previous repeated value by other than one.at n=9A269531
- Numbers k such that k and 4k, taken together, contain all digits 1 though 9 at least once.at n=19A346135