8928
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 36
- Divisor Sum
- 26208
- Proper Divisor Sum (Aliquot Sum)
- 17280
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2880
- Möbius Function
- 0
- Radical
- 186
- Omega Function (Ω)
- 8
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 47
- 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
- a(0) = 1, a(1) = 4; thereafter a(n)*(2n + 10) - a(n-1)*(11n + 35) + a(n-2)*(8n + 2) + a(n-3)*(15n + 7) + a(n-4)*(4n - 2) = 0.at n=7A001559
- a(n) = Sum_{m=0..n} (Sum_{k=0..m} binomial(n,k))^3 = (n+2)*2^(3*n-1) - 3*2^(n-2)*n*binomial(2*n,n).at n=4A007403
- a(n) = floor( n*(n-1)*(n-2)/28 ).at n=64A011910
- Number of triples of different integers from [ 2,n ] with no global factor.at n=40A015618
- Cycle class sequence c(2n) (the number of true cycles of length 2n in which a certain node is included) for zeolite VFI = VPI-5 [ Al18P18O72 ]. 42 H2O.at n=5A019063
- Numbers m such that uphi(sigma(m)) = 2m, where the unitary phi function (A047994) is defined by: if x = p1^r1*p2^r2*p3^r3*... then uphi(x) = (p1^r1 - 1)*(p2^r2 - 1)*(p3^r3 - 1)*...at n=9A030165
- Divide even numbers into groups with prime(n) elements and add together.at n=10A034959
- Number of step shifted (decimated) sequences using a maximum of two different symbols.at n=15A056371
- a(n) = 18*(n - 2)*(2*n - 5).at n=16A060787
- Numbers k such that nusigma(usigma(k)) = 2k, where usigma(k) is the sum of unitary divisors of k (A034448) and nusigma(k) is the sum of non-unitary divisors of k (A048146).at n=2A063891
- Triangle T(n,k) giving number of hill-free Dyck paths of length 2n and having height of first peak equal to k.at n=58A065602
- Numbers n such that sigma(n) is congruent to n mod phi(n).at n=14A066679
- Numbers n such that the number of primes not exceeding sigma(n) equals phi(n), i.e., pi(sigma(n)) = phi(n).at n=9A067787
- Numbers k such that the sum over the prime divisors of k equals the number of divisors of k.at n=35A069234
- a(1)=1, a(n) is the smallest number >= a(n-1) such that the simple continued fraction for S(n) = 1/a(1) + 1/a(2) + ... + 1/a(n) contains exactly n elements.at n=35A071012
- Omega(n) = Omega(n-1)^3, where Omega(m) (A001222) denotes the number of prime factors of m, counting multiplicity.at n=38A076155
- Numbers k such that average of prime(k) and prime(k+1) is a perfect square.at n=38A076692
- A unitary phi reciprocal amicable number: consider two different numbers r, s which satisfy the following equation for some integer k: uphi(r) = uphi(s) = (1/k) * r * s / (r-s); or equivalently, 1/uphi(r) = 1/uphi(s) = k * (1/s - 1/r); sequence gives s numbers.at n=12A080767
- Positive integers n such that n^11 + 1 is semiprime.at n=40A105122
- 8-almost primes p*q*r*s*t*u*v*w relatively prime to p+q+r+s+t+u+v+w.at n=33A110296