9159
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 12672
- Proper Divisor Sum (Aliquot Sum)
- 3513
- 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
- 5880
- Möbius Function
- -1
- Radical
- 9159
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 197
- 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
- no
- Odd
- yes
Appears in sequences
- Number of strict 3rd-order maximal independent sets in cycle graph.at n=42A007392
- Eight iterations of Reverse and Add are needed to reach a palindrome.at n=35A015988
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite DDR = Deca-dodecasil 3R[Si120O240]qR starting with a T7 atom.at n=12A019109
- Numbers which need eight 'Reverse and Add' steps to reach a palindrome.at n=30A065213
- Numbers n such that [A070080(n), A070081(n), A070082(n)] is an acute integer triangle with integer area.at n=24A070146
- Integer part of the area of consecutive prime sided isosceles triangles.at n=33A097442
- a(n) = (10^k - n)(10^k + n), where k is the number of digits in n.at n=28A110397
- a(n) = (5*n-7)*(n-1).at n=43A147874
- Row sums of triangle A156837.at n=59A156838
- a(n) = (9 + 14*n + 12*n^2 + 4*n^3)/3.at n=18A166911
- First number in the n-th row of A172002.at n=37A168388
- a(n) = number of 9-digit primes with digit sum n, where n runs through the non-multiples of 3 in the range [2..80].at n=7A178884
- Monotonic ordering of set S generated by these rules: if x and y are in S then 5xy-x-y is in S, and 1 is in S.at n=38A192528
- Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^2+x^2+y^2>2n.at n=21A211644
- Number of 0..4 arrays of length n with each element unequal to at least one neighbor, with new values introduced in 0..4 order.at n=8A221455
- T(n,k)=Number of 0..k arrays of length n with each element unequal to at least one neighbor, with new values introduced in 0..k order.at n=74A221459
- a(n) = a(n-2) + a(n-3) + a(n-4) with a(0) = 0, a(1) = a(2) = 1, a(3) = 0.at n=27A277252
- Least integer k such that k/2^n > sqrt(5).at n=12A293332
- The integer k that minimizes |k/2^n - sqrt(5)|.at n=12A293333
- The sum of the numbers on straight lines of incrementing length n when drawn over numbers of the square spiral, where each line contains numbers which sum to the minimum possible value, and each number on the spiral can only be in one line. If two or more lines exist with the same sum the one containing the smallest number is chosen.at n=22A340974