8105
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 9732
- Proper Divisor Sum (Aliquot Sum)
- 1627
- 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
- 6480
- Möbius Function
- 1
- Radical
- 8105
- 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
- 70
- 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
- a(n) = Sum_{k=1..n} floor((n/k) * floor((n/k) * floor(n/k))).at n=18A024922
- a(n) = (d(n) - r(n))/5, where d = A026037 and r is the periodic sequence with fundamental period (1,2,0,2,0).at n=47A026039
- Numbers k such that the least term in the periodic part of the continued fraction for sqrt(k) is 36.at n=4A031714
- Denominators of continued fraction convergents to sqrt(391).at n=10A041743
- Numbers k such that 10*k-1, 10*k-3, 10*k-7 and 10*k-9 are all prime.at n=32A064975
- Molien series for genus 2 complete weight enumerators of self-dual codes over GF(3).at n=10A092069
- Positions of 4's in A038800 with offset 1.at n=33A115095
- First semiprime after e^n.at n=9A117879
- Triangle read by rows: T(n,k) = number of unlabeled free bicolored trees with n nodes (n >= 1) and k (1 <= k <= floor(n/2), except k = 0 if n = 1 ) nodes of one color and n-k nodes of the other color (the colors are interchangeable).at n=63A122087
- a(n) = n_{n^2}.at n=44A122625
- a(n) = 25*n^2 + 5.at n=17A158445
- Bisect A053445 then calculate the first differences of the resulting sequence.at n=31A160643
- Averages of four consecutive odd squares.at n=43A173960
- Fibonacci-type sequence based on bitwise inclusive-or: a(0) = 0, a(1) = 1 and a(n) = a(n-1) + (a(n-1) or a(n-2)).at n=13A182202
- Numbers n such that 4n+3 is a palindromic prime.at n=28A193419
- G.f. A(x) satisfies A(x)+A(x)^2+A(x)^3 = (1-sqrt(1-4*x))/2.at n=11A212260
- Number of cyclotomic cosets of 7 mod 10^n.at n=11A220019
- Numbers k such that k^2 - k - 1, k^3 - k - 1, and k^4 - k - 1 are all prime.at n=31A236171
- Number of compositions of n such that the first part is 1 and the second differences of the parts are in {-3,...,3}.at n=17A239553
- Row sums of triangle A027420.at n=38A241944