8620
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 18144
- Proper Divisor Sum (Aliquot Sum)
- 9524
- 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
- 3440
- Möbius Function
- 0
- Radical
- 4310
- Omega Function (Ω)
- 4
- 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
- 171
- 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(n) = floor( n*(n-1)*(n-2)/29 ).at n=64A011911
- a(n) = 1*t(n) + 2*t(n-1) + ... + k*t(n+1-k), where k=floor((n+1)/2) and t = A002808 (composite numbers).at n=39A023863
- a(n) = s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (natural numbers), t = (composite numbers).at n=38A024860
- a(n) = Sum{T(i,j)}, 0<=j<=i, 0<=i<=2n, T given by A026568.at n=9A026583
- Numbers in which 0,1,2,3,4,5 all occur in base 6.at n=10A031947
- Number of binary codes (not necessarily linear) of length n with 4 words.at n=14A034199
- Digitally balanced numbers in base 6: equal numbers of 0's, 1's, ..., 5's.at n=10A049357
- 13-gonal (or tridecagonal) numbers: a(n) = n*(11*n - 9)/2.at n=40A051865
- Numbers k such that 291*2^k + 1 is prime.at n=26A053362
- First differences of the Poly-Bernoulli numbers B_n^(k) with k=-2 (A027649).at n=8A053581
- McKay-Thompson series of class 45b for Monster.at n=51A058686
- Number of permutations satisfying -k<=p(i)-i<=r and p(i)-i not in I, i=1..n, with k=2, r=3, I={-1,0,1}.at n=41A080002
- Area of annuli of consecutive integer thickness.at n=13A114378
- Numbers with even decimal digits in decreasing order.at n=27A119261
- Poincaré series [or Poincare series] P(T_{5,2}; x).at n=9A124617
- Greatest number m such that the fractional part of (10/9)^A153694(n) <= 1/m.at n=7A153698
- Numbers k such that k^2 == 2 (mod 23^2).at n=32A156849
- Sums of least knight's moves from (0,0) to points in the square lattice [-n,n]x[-n,n].at n=17A183047
- Number of (w,x,y) with all terms in {0,...,n} and |w-x| != |x-y|.at n=20A212960
- Number of 5 X 5 0..n matrices with each 2 X 2 subblock idempotent.at n=39A224667