8500
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 19656
- Proper Divisor Sum (Aliquot Sum)
- 11156
- 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
- 3200
- Möbius Function
- 0
- Radical
- 170
- Omega Function (Ω)
- 6
- 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
- 127
- 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
- Stirling numbers of the first kind: s(n+2, n).at n=15A000914
- Endpoints in trees with n nodes.at n=12A003228
- Stirling numbers of first kind S1(17,n).at n=14A011527
- a(n) = floor(binomial(n,5)/5).at n=24A011851
- a(n) = floor( n*(n-1)*(n-2)*(n-3)/25 ).at n=23A011935
- a(n) = floor(n*(n-1)*(n-2)*(n-3)/30).at n=24A011940
- Self-convolution of array T given by A026648.at n=7A026971
- Table read by rows: list of even numbers to the right of the central elements of the (2,3)-Pascal triangle A029600.at n=43A029617
- Even numbers to left of central elements of the (3,2)-Pascal triangle A029618.at n=41A029631
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 46.at n=40A031544
- Schoenheim bound L_1(n,n-5,n-6).at n=17A036837
- Numbers whose base-5 representation contains exactly three 0's and two 3's.at n=23A045201
- Generalized Stirling number triangle of first kind.at n=18A048176
- Triangle of coefficients of polynomials (rising powers) useful for convolutions of A000204(n+1), n >= 0 (Lucas numbers).at n=11A061189
- Numbers k such that Sum_{i=1..k} phi(i)/gcd(k,i) is an integer.at n=36A066969
- Numbers k such that the sum over the prime divisors of k equals the number of divisors of k.at n=31A069234
- Expansion of (1-x)^(-1)/(1-x-2*x^2-2*x^3).at n=11A077863
- Sequence resulting from a sum of three repeated binomial(n+3,4) sequences.at n=29A093039
- Numbers n that are the hypotenuse of exactly 10 distinct integer-sided right triangles, i.e., n^2 can be written as a sum of two squares in 10 ways.at n=13A097225
- Bisection of A001157: a(n) = sigma_2(2n-1).at n=45A099978