8915
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 10704
- Proper Divisor Sum (Aliquot Sum)
- 1789
- 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
- 7128
- Möbius Function
- 1
- Radical
- 8915
- 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
- 47
- 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
- Number of partitions of n into parts not of the form 23k, 23k+7 or 23k-7. Also number of partitions with at most 6 parts of size 1 and differences between parts at distance 10 are greater than 1.at n=33A035995
- Triangle read by rows: T(n,k) is the number of unlabeled nonseparable (or 2-connected) loopless multigraphs with n edges on k nodes and degree >= 3 at each node, n >= 3, 2 <= k <= floor(2*n/3).at n=48A046752
- Series for first parallel moment of square lattice bond percolation near a wall.at n=12A056575
- Triangle, read by rows, defined by T(n,k) = T(n-1,k) + T(n,k-1) for nk>0, where T(n,0) = T(n-1,0) + T(n-1,n-1) and T(n,n) = T(n,n-1) for n>0 with T(0,0)=1.at n=37A129577
- a(n) = Sum_{k=1..n^2} d(k), d(k) = number of divisors of k (A000005).at n=34A175346
- Numbers k that divide the sum of digits of 13^k.at n=27A175525
- Semiprimes which are the arithmetic mean of three consecutive primes.at n=39A242218
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 966", based on the 5-celled von Neumann neighborhood.at n=30A273837
- Numbers n for which |n/zeta(2) - Q(n)| sets a new record, where Q(x) is the number of squarefree numbers up to x.at n=33A275390
- Number of inequivalent leaf-colorings of planted achiral trees with n nodes.at n=16A318228
- Numerators of sequence whose Dirichlet convolution with itself yields A342920.at n=74A346103
- a(n) is the number of reducible monic quartic polynomials (x^4 + r*x^3 + s*x^2 + t*x + u) with integer coefficients bounded by naïve height n (abs(r), abs(s), abs(t), abs(u) <= n).at n=6A358399
- a(n) = [x^n] Product_{k=1..n} (x^(k^4) + 1/x^(k^4)).at n=33A368206
- Numbers k such that (the concatenation of the first k positive even numbers) + 1 is prime.at n=5A387245