6517
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 8000
- Proper Divisor Sum (Aliquot Sum)
- 1483
- 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
- 5292
- Möbius Function
- 0
- Radical
- 133
- Omega Function (Ω)
- 4
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 44
- 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
- a(n) = Sum_{k=1..n-1} lcm(k,n-k).at n=38A006580
- Expansion of e.g.f.: cosh(log(x+1)-tanh(x))=1+3/4!*x^4-40/5!*x^5+250/6!*x^6-1008/7!*x^7...at n=8A013291
- Pseudoprimes to base 18.at n=35A020146
- Numbers k such that the continued fraction for sqrt(k) has period 90.at n=6A020429
- Numbers whose sum of divisors is a cube.at n=34A020477
- a(n) = [ a(n-1)/a(1) ] + [ a(n-3)/a(3) ] + [ a(n-5)/a(5) ] + ..., for n >= 3.at n=23A022860
- Numbers n such that n and n-1 are differences between 2 positive cubes in at least one way.at n=8A038595
- Numbers ending with '7' that are the difference of two positive cubes.at n=35A038862
- Numbers whose base-5 representation contains exactly two 0's and three 2's.at n=32A045183
- a(n) = T(2n-1,n), array T given by A048201.at n=40A048208
- Numbers with a sum of digits equal to their greatest prime factor.at n=43A052021
- Numbers k such that sopf(k) = d(k) where d(k) = A001223(k) and sopf(k) = A008472(k).at n=21A064010
- 1/20 the number of colorings of an n X n square array with 20 colors.at n=1A068270
- q-factorial numbers 3!_q.at n=18A069778
- Rounded volume of a regular octahedron with edge length n.at n=24A071400
- Numbers n such that sopf(phi(n)) = phi(sopf(n)), where sopf(x) = sum of the distinct prime factors of x.at n=22A076531
- p(p^2-p+1) as p runs through the primes.at n=7A083558
- Numbers n such that n is not the power of a prime and such that for every prime divisor p of n, p-1 divides n-1.at n=23A087442
- Number of Pythagorean quadruples mod n; i.e., number of solutions to w^2 + x^2 + y^2 = z^2 mod n.at n=18A096018
- Numbers n such that every digit occurs at least once in n^3.at n=17A119735