17622
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 42120
- Proper Divisor Sum (Aliquot Sum)
- 24498
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5280
- Möbius Function
- 0
- Radical
- 5874
- Omega Function (Ω)
- 5
- 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
- yes
- Harshad Number
- yes
- 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
- Functional determinants; partitions of partitions; Euler transform applied twice to all 1's sequence.at n=15A001970
- Number of bifix-free (or primary, or unbordered) words of length n over a two-letter alphabet.at n=16A003000
- Moebius transform of Fibonacci numbers.at n=21A007436
- Fibonacci sequence beginning 3, 16.at n=16A022126
- Number of partitions satisfying cn(0,5) + cn(1,5) + cn(4,5) < cn(2,5) + cn(3,5).at n=42A039880
- Number of binary words of length n (beginning with 0) whose autocorrelation function is the indicator of a singleton.at n=16A045690
- Integers formed from the reduced residue sets of even numbers and Fibonacci numbers.at n=10A063683
- a(n) = Sum_{1<=k<=n, gcd(k,n)=1} Fibonacci(k).at n=21A070964
- a(n)/4^n is the measure of the subset of [0,1] remaining when all intervals of the form [b/2^m - 1/2^(2m), b/2^m + 1/2^(2m)] have been removed, with b and m positive integers, b < 2^m and m <= n.at n=8A107284
- a(n) = (72 - 258*n + 601*n^2 - 264*n^3 + 33*n^4)/4.at n=9A108642
- Convolution of A066983 with the double Fibonacci sequence A103609.at n=21A121364
- Triangle read by rows where the n-th row is the first row of M^n, with M the (n+1)-by-(n+1) matrix with (3,1,3,1,3,1,...) on its main diagonal and (1,3,1,3,1,3,...) on its superdiagonal.at n=40A124573
- a(n) = a(n-1) + floor(a(n-2)/3) with a(0)=2, a(1)=3.at n=40A182229
- Number of nXnXn 0..6 triangular arrays with each element x equal to the number its neighbors equal to 4,4,1,0,1,0,0 for x=0,1,2,3,4,5,6.at n=5A197783
- 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=29A205859
- s(k)-s(j), where the pairs (k,j) are given by A205872 and A205873, and s(k) denotes the (k+1)-st Fibonacci number.at n=16A205874
- Number of length n+4 0..2 arrays with at most two downsteps in every 4 consecutive neighbor pairs.at n=4A255618
- T(n,k)=Number of length n+k 0..2 arrays with at most two downsteps in every k consecutive neighbor pairs.at n=32A255622
- Number of length n+5 0..2 arrays with at most two downsteps in every n consecutive neighbor pairs.at n=3A255627
- a(n) = 69*2^n - 42 (n>=1).at n=7A304510