10685
domain: N
Properties
Digital Properties
- Digit Count
- 5
- 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
- 12828
- Proper Divisor Sum (Aliquot Sum)
- 2143
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8544
- Möbius Function
- 1
- Radical
- 10685
- 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
- 47
- 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
- Related to series-parallel networks.at n=12A001572
- Numbers k such that the continued fraction for sqrt(k) has period 41.at n=21A020380
- a(n) = T(n, 2*n-6), T given by A027960.at n=12A027968
- Discriminants of real quadratic fields with class number 2 and related continued fraction period length of 9.at n=19A051974
- a(n) = ( A077059(n)^2 + A077060(n)^2 )^(1/3).at n=32A077061
- a(1)=a(2)=a(3)=1; a(n)=|a(n-2)+a(n-3)|-2*a(n-1).at n=16A080206
- Ordered hypotenuses of primitive Pythagorean triangles having legs that add up to a square.at n=15A088319
- a(0)=1, a(1)=5; a(n) = 6*a(n-1) + 5*a(n-2) for n > 1.at n=5A091928
- Triangle read by rows: T(n,k) is the number of Dyck paths of semilength n having k UUUU's starting at level 0.at n=18A135309
- Number of Dyck paths of semilength n having no UUUU's starting at level 0.at n=10A135310
- Numbers n with property that A077116(n) is nonzero square.at n=41A154101
- a(n) = Sum_{i=1..n} ( Product_{k|i} d(k) ), where d(n) = A000005(n).at n=27A237349
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 710", based on the 5-celled von Neumann neighborhood.at n=40A273423
- Numbers k such that k![4] - 256 is prime, where k![4] = A007662(k) = quadruple factorial.at n=32A329177
- Indices of records in A347113.at n=22A347308
- a(n) is the index of the smallest n-gonal pyramidal number with binary weight n.at n=30A359092
- a(n) = Sum_{k=1..n} sigma(n*k).at n=20A372710
- Number of edges in a complete bipartite graph where the vertices in the two parts are placed on opposite sides of a parabola at integer x coordinates |x| = 1, 2, ...n.at n=12A392427