8705
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 10452
- Proper Divisor Sum (Aliquot Sum)
- 1747
- 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
- 6960
- Möbius Function
- 1
- Radical
- 8705
- Omega Function (Ω)
- 2
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 171
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- Squarefree Number
- yes
- 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
- Pseudoprimes to base 59.at n=36A020187
- (1/binomial(0,0) - 1/binomial(2,1) + ... + d/binomial(2n,n))*L, where d = (-1)^n, L = LCM{binomial(0,0), binomial(2,1),..., binomial(2n,n)}.at n=6A025542
- a(n) = Sum_{ d divides n } (n/d)^(3d).at n=7A073706
- a(n) = 512*n + 1.at n=17A076338
- Expansion of (5 - 9*x + 6*x^2)/(1-x)^4.at n=29A080957
- Indices k where A057176(k) = 4.at n=21A086838
- Triangle of numbers related to the generalized Catalan sequence C(2;n+1)=A064062(n+1), n>=0.at n=47A113647
- A106486-encodings of combinatorial games with value 1.at n=36A125992
- Numbers k such that k and k^2 use only the digits 0, 2, 5, 7 and 8.at n=16A136916
- a(n) = A145812(2n-1).at n=40A145849
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 0, -1), (1, -1, -1), (1, -1, 0), (1, 1, 1)}.at n=8A149511
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 0), (-1, 0, -1), (0, -1, 1), (1, -1, -1), (1, 1, 1)}.at n=8A149512
- Similar to A072921 but starting with 4.at n=38A152233
- 10^n-6^n+1.at n=4A155653
- a(n) = 256*n + 1.at n=33A158231
- a(n) = 34*n^2 + 1.at n=16A158586
- a(n) = 14*a(n-1) - 47*a(n-2) for n > 1; a(0) = 1, a(1) = 11.at n=4A163413
- a(n) = a(n-1)+a(n-2)+a(n-3)+(8*n^3-48*n^2+112*n-96)/3 with a(0)=0, a(1)=0 and a(2)=1.at n=10A180670
- Number of (n+3) X 5 binary arrays with every 4 X 4 subblock commuting with each horizontal and vertical neighbor 4 X 4 subblock.at n=13A188098
- Potential magic constants of 7 X 7 magic squares composed of consecutive primes.at n=23A188536