9171
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 6
- Divisor Sum
- 13260
- Proper Divisor Sum (Aliquot Sum)
- 4089
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6108
- Möbius Function
- 0
- Radical
- 3057
- Omega Function (Ω)
- 3
- 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
- 153
- 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
- no
- Odd
- yes
Appears in sequences
- Number of points of norm <= n in cubic lattice.at n=13A000605
- a(n) = s(1)s(n) + s(2)s(n-1) + ... + s(k)s(n+1-k), where k = [ (n+1)/2 ], s = (Lucas numbers).at n=13A024469
- a(n) = floor(C(2n,n)/2^n).at n=16A024502
- a(n) = s(1)*s(n) + s(2)*s(n-1) + ... + s(k)*s(n-k+1), where k = [n/2], s = (Lucas numbers).at n=13A025089
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 95.at n=12A031593
- a(n) = a(n-1) + Sum_{k=0..n-3} a(k) for n >= 2, a(0)=1, a(1)=2.at n=17A049853
- Closed 3-dimensional ball numbers (version 1): a(n)= number of integer points (i,j,k) contained in a closed ball of diameter n, centered at (0,0,0).at n=26A053591
- One half of second column of Lucas bisection triangle (odd part).at n=6A061171
- Convolution of L(n+1) := A000204(n+1) (Lucas), n>=0, with L(n+8), n>=0.at n=6A067986
- Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=2, r=3, I={-1,0}.at n=22A080008
- a(1) = 1, a(2) = 2, a(3) = 3, a(n+3) = a(n) + a(n+1).at n=31A084338
- Positions at which the sum of the digits of e up to that point equals the sum of the digits of Pi up to that point.at n=20A131660
- Linear recurrence a(n) = a(n-3) + 2a(n-5), starting from all-one initial conditions.at n=37A133683
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 1, -1), (0, 0, 1), (1, -1, 1), (1, 1, -1)}.at n=9A148381
- Fibonacci sequence beginning 13, 7.at n=15A206611
- Total number of parts of multiplicity 7 in all partitions of n.at n=39A222707
- Numbers m such that A000041(m) is of the form 2^7 * k for odd k.at n=43A278784
- Partial sums of A299258.at n=22A299264
- Numbers that are the sum of five third powers in exactly nine ways.at n=31A345186
- Numbers that are the sum of six fourth powers in exactly three ways.at n=41A345815