10856
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
- 16
- Divisor Sum
- 21600
- Proper Divisor Sum (Aliquot Sum)
- 10744
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5104
- Möbius Function
- 0
- Radical
- 2714
- Omega Function (Ω)
- 5
- 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
- 55
- 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
- Larger of amicable pair.at n=5A002046
- Numbers k such that phi(k + 12) | sigma(k) for k not congruent to 0 (mod 3).at n=37A015850
- Consider all integer triples (i,j,k), j >= k > 0, with i^3 = binomial(j+2,3) + binomial(k+2,3), ordered by increasing i; sequence gives i values.at n=15A054208
- Amicable numbers.at n=11A063990
- Upper triangular region of the table A073345.at n=72A073429
- -log(1-Sum_{n>0} x^n/n^2) = Sum_{n>=0} a(n)*x^n/n!^2.at n=4A074708
- Let pi be an unrestricted partition of n with the summands written in binary notation. a(n) is the number of such partitions whose binary representation has an odd number of binary ones.at n=37A102437
- Numbers n such that 2*10^n-3 is prime.at n=17A102947
- Larger member of an infinitary amicable pair.at n=6A126170
- Infinitary amicable numbers.at n=12A127664
- a(0)=0. a(n) = a(n-1) + sum of positive integers which are <= n and not part of the sequence.at n=41A129694
- Convolution of A000108 (Catalan numbers) and A001764 (ternary trees): a(n) = Sum_{k=0..n} C(2k,k) * C(3(n-k),n-k) / [(k+1)(2(n-k)+1)].at n=7A130579
- 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, 1, 0), (0, 0, -1), (1, 0, 0), (1, 1, 1)}.at n=7A150768
- Triangle read by rows where T(n,k) is the number of factorizations of (n+1)! into k distinct factors.at n=40A157836
- Half the difference between the larger and smaller term of the n-th amicable pair.at n=38A162884
- The larger amicable number corresponding to A180330(n).at n=1A180331
- Irregular triangle in which row n consists of the larger of pairs of amicable numbers of the form 2^n pq, with p and q odd primes.at n=2A180651
- Largest members of k-sociable cycles of order r.at n=11A183013
- Conjectured list of multisociable numbers.at n=17A183019
- Number of 4-step left-handed knight's tours (moves only out two, left one) on an n X n board summed over all starting positions.at n=20A187174