9555
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
- 3
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 19152
- Proper Divisor Sum (Aliquot Sum)
- 9597
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 4032
- Möbius Function
- 0
- Radical
- 1365
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 104
- 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
- Odd abundant numbers (odd numbers m whose sum of divisors exceeds 2m).at n=21A005231
- a(n) = n^2*(n^2 - 1)/4.at n=14A006011
- Odd primitive abundant numbers.at n=16A006038
- a(n) is the least k > 0 such that k and 3k are anagrams in base n (written in base 10).at n=10A023095
- a(n) = 13*(n+1)*binomial(n+2,13)/2.at n=2A027786
- a(n) = (1/4)*floor(n/2)*floor((n-1)/2)*floor((n-2)/2)*floor((n-3)/2).at n=30A028723
- Numbers having three 5's in base 10.at n=35A043511
- Odd composite numbers divisible by the sum of their prime factors (counted with multiplicity).at n=29A046347
- 18-gonal (or octadecagonal) numbers: a(n) = n*(8*n-7).at n=35A051870
- Truncated triangular pyramid numbers: a(n) = Sum_{k=4..n} (k*(k+1)/2 - 9).at n=34A051937
- Numbers k such that k | sigma_9(k) - phi(k)^9.at n=25A055703
- n is odd and sum of digits of n equals the numbers of divisors of n.at n=40A057532
- Number of orbits of length n under the full 14-shift (whose periodic points are counted by A001023).at n=3A060217
- Numbers n such that sopf(phi(n)) = phi(sopf(n)), where sopf(x) = sum of the distinct prime factors of x.at n=29A076531
- a(n) is the smallest number k such that A033880(k)= n, or 0 if no such number exists, where A033880 is the abundance of k.at n=42A082731
- Odd numbers k such that abs(sigma(k)-2k) <= sqrt(k). Abundance-radius = abs(sigma(k)-2k) does not exceed square root of k and k is odd.at n=9A087415
- a(n) = S(n,5), where S(n,m) = Sum_{k=0..n} binomial(n,k)*Fibonacci(m*k).at n=4A087453
- a(n) = smallest number x such that sigma(x) = 2x + 2n.at n=21A087998
- Take the list t(n,0) = {1,...,n}; denote by t(n,j) this list after rotating to left (or right) by j positions. Calculate inner product of t(n,0) and t(n,j) and denote the value by s(n,j). Compute this inner product for all j = 1..n and choose the smallest. This is a(n).at n=34A088003
- Sum of digits of numbers between 0 and (7/9)*(10^n-1).at n=3A089908