8505
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 17472
- Proper Divisor Sum (Aliquot Sum)
- 8967
- 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
- 3888
- Möbius Function
- 0
- Radical
- 105
- Omega Function (Ω)
- 7
- 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
- 83
- 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
- Denominators of coefficients of Green function for cubic lattice.at n=3A003302
- Odd abundant numbers (odd numbers m whose sum of divisors exceeds 2m).at n=18A005231
- Dimensions of representations by Witt vectors.at n=7A006973
- Sextuple factorial numbers: a(n) = Product_{k=0..n-1} (6*k+3).at n=4A011781
- Expansion of e.g.f. theta_3^(9/2).at n=5A015669
- a(n) = a(n-1) + a(n-2) + 1 for n>1, a(0)=0, a(1)=7.at n=16A022312
- a(n) = Sum_{k=m..n} T(k,n-k), where m = floor((n+1)/2); a(n) is the n-th diagonal-sum of left justified array T given by A027935.at n=23A027947
- Number of free orthoplex n-ominoes with cell centers determining n-2 space.at n=8A036367
- Number of partitions satisfying cn(2,5) <= 1 and cn(3,5) <= 1.at n=40A039855
- Odd numbers divisible by exactly 7 primes (counted with multiplicity).at n=5A046320
- Odd composite numbers divisible by the sum of their prime factors (counted with multiplicity).at n=27A046347
- a(n) = ((6*n+9)(!^6))/9(!^6), related to A034723 (((6*n+3)(!^6))/3 sextic, or 6-factorials).at n=3A053102
- Expansion of (1 + 4*x + 14*x^2 + 34*x^3 + 63*x^4 + 80*x^5 + 87*x^6 + 68*x^7 + 42*x^8 + 20*x^9 + 7*x^10) / ((1 - x)*(1 - x^2)^2*(1 - x^3)^2*(1 - x^4)).at n=11A055384
- Denominators in an asymptotic expansion of Ramanujan.at n=3A065973
- Triangle formed by multiplying Stirling numbers of 2nd kind S2(n,m) (A008277) by m+1.at n=31A069138
- Numbers k such that tau_3(k) (the number of ordered factorizations of k as k = r*s*t) divides k.at n=37A069147
- a(n) = A061680(n!).at n=35A069785
- Numbers k such that the sum of exponents of k is equal to the greatest prime factor of k; a(1)=1.at n=45A071929
- Numbers k such that tau(k) = sigma(sopf(k)).at n=42A075867
- a(1) = 1, a(n+1) is the smallest odd multiple of a(n) (other than a(n) itself) in which the digits are alternately even and odd.at n=6A078226