10806
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 21624
- Proper Divisor Sum (Aliquot Sum)
- 10818
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 3600
- Möbius Function
- -1
- Radical
- 10806
- Omega Function (Ω)
- 3
- 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
- 73
- Smith Number
- yes
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) = floor( n*(n-1)*(n-2)/19 ).at n=60A011901
- Total number of prime parts in all partitions of n.at n=26A037032
- Numbers k such that (3^k + 5)/2 is prime.at n=22A058960
- a(n) = A086323(n)/n.at n=17A086442
- Numbers n such that n/6 and prime(n)+/-n are all primes.at n=19A105550
- Sum of the first n n-digit primes less n*10^(n-1).at n=21A114053
- Numbers that are the sum of two reversed consecutive primes in more than one way.at n=36A162705
- 6 times centered hexagonal numbers: 18*n*(n+1) + 6.at n=24A164016
- Sums of 3 consecutive semiprimes.at n=39A173968
- Sums of three consecutive numbers each of which is the product of two distinct primes and each of which has no exponent greater than one for either of its two prime factors.at n=37A173969
- Number of increasing sequences of n integers x(1),...,x(n) with values in 1..2*n such that x(j) divides x(k) if j divides k.at n=41A180384
- Number of nondecreasing arrangements of 4 nonzero numbers in -(n+2)..(n+2) with sum zero.at n=33A188334
- Number of (w,x,y) with all terms in {0,...,n} and |w-x| + |x-y| + |y-w| < w+x+y.at n=24A213488
- Compositions of n into parts 3, 5 and 7.at n=46A245367
- Total number of points on a sphere when both poles are on an x by x grid where x=8*n+1.at n=36A254527
- The number of edges inside a cross with width 3 and height n (see Comments in A331455 for definition) formed by the straight line segments mutually connecting all vertices and all points.at n=11A330851
- Number of edges in a hexagon when n internal hexagons are drawn between the 6n points that divide each side into n+1 equal parts.at n=30A357198
- a(0) = 1, a(1) = 0, a(2) = 1; a(n) = a(n-1) + Sum_{k=0..n-3} a(k) * a(n-k-3).at n=17A357307
- Number of ways to write a + b + c = d + e = f with {a,b,c,d,e,f} a subset of [n] of size 6 and a < b < c and d < e.at n=36A362717