17706
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
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 38304
- Proper Divisor Sum (Aliquot Sum)
- 20598
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5424
- Möbius Function
- 1
- Radical
- 17706
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- 141
- 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
- Generalized Fibonacci numbers A_{n,2}.at n=31A006207
- Square of triangular matrix A104445, read by rows, where X=A104445 satisfies: SHIFT_LEFT_UP(X) = X^2 - X + I.at n=59A104446
- Number of monocyclic skeletons with n carbon atoms and a ring size of 8.at n=9A120795
- Minimal value of A007947(m*(11^n-m)) with m coprime to 11.at n=6A147798
- a(n) = Least i in range [A165598(n),A165598(n+1)] for which abs(A165597(i)) gets the maximum value in that range.at n=5A165599
- a(n) = Fibonacci(n) - 5.at n=17A167616
- s(k)-s(j), where the pairs (k,j) are given by A205857 and A205858, and s(k) denotes the (k+1)-st Fibonacci number.at n=28A205859
- Numbers that match polynomials over {0,1} that have a factor containing -3 as a coefficient; see Comments.at n=23A208182
- Start with a single pentagon; at n-th generation add a pentagon at each expandable vertex; a(n) is the sum of all label values at n-th generation. (See comment for construction rules.)at n=18A247619
- Number of integer partitions of n whose parts do not have choosable sets of integer partitions.at n=37A387134
- a(n) = Sum_{k=0..floor(n/6)} (7*k+1) * binomial(2*n-5*k+1,n-6*k)/(2*n-5*k+1).at n=10A390481