17899
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 34
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 20464
- Proper Divisor Sum (Aliquot Sum)
- 2565
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 15336
- Möbius Function
- 1
- Radical
- 17899
- Omega Function (Ω)
- 2
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 123
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- "DFJ" (bracelet, size, labeled) transform of 1,3,5,7...at n=8A032212
- "EFJ" (unordered, size, labeled) transform of 1,3,5,7,...at n=8A032300
- When A032523 is a maximum; or, A091657 less duplicates.at n=16A091658
- Number of n X n binary arrays symmetric under 180 degree rotation with all ones connected only in a 0100-1111-0100 pattern in any orientation.at n=10A146380
- Positions of zeros in A165597.at n=22A165598
- G.f.: A(x) = Sum_{n>=0} (3n)!/(n!)^3 * x^(3n)/(1-x-x^2)^(3n+1).at n=9A181545
- Least integer having a larger digital sum than the previous term and such that 10^(n-1) + a(n) is a prime.at n=15A199190
- Number of nXnXn 0..6 triangular arrays with each element x equal to the number its neighbors equal to 1,4,0,0,2,2,0 for x=0,1,2,3,4,5,6.at n=5A203110
- Indices of record values in A216476.at n=27A216502
- Values of n such that L(18) and N(18) are both prime, where L(k) = (n^2+n+1)*2^(2*k) + (2*n+1)*2^k + 1, N(k) = (n^2+n+1)*2^k + n.at n=37A227521
- Expansion of Product_{k>=1} 1/(1 - k*(x^(2*k+1))).at n=40A266138
- Number of nX4 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2, 3 or 5 neighboring 1s.at n=5A297798
- T(n,k) = Number of n X k 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2, 3 or 5 neighboring 1's.at n=41A297802
- Number of 6Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 2, 3 or 5 neighboring 1s.at n=3A297806
- a(n) = A306302(n)/2.at n=21A331756
- a(n) is the least number k whose sum of digits in base 10 is n and that is palindromic in base n, or -1 if no such number exists.at n=31A375387