12826
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 21546
- Proper Divisor Sum (Aliquot Sum)
- 8720
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5720
- Möbius Function
- 0
- Radical
- 1166
- Omega Function (Ω)
- 4
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 63
- 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
- Expansion of 1/((1-6x)(1-7x)(1-9x)(1-12x)).at n=3A028206
- Multiplicity of highest weight (or singular) vectors associated with character chi_8 of Monster module.at n=42A034396
- a(n)=a(n-1)+a(m), where m=2n-2-2^(p+1) and 2^p<n-1<=2^(p+1), for n >= 4.at n=30A050063
- Number of dissections of a convex polygon by nonintersecting diagonals into polygons with even number of sides and having a total number of n edges (sides and diagonals).at n=19A067955
- Numbers n such that zero is never reached by iterating the mapping k -> abs(reverse(lpd(k))-reverse(gpf(k))). lpd(k) is the largest proper divisor and gpf(k) is the largest prime factor of k.at n=35A076425
- Number of humps in all Motzkin paths of length n. (A hump is an upstep followed by 0 or more flatsteps followed by a downstep.)at n=11A097861
- Minimal number m such that Sum_digits(n*m)=n.at n=45A131382
- Number of (n+2) X 8 0..1 matrices with each 3 X 3 subblock idempotent.at n=13A224557
- Total number of parts in all overpartitions of n.at n=15A235792
- Expansion of (1/2)*(1/(x+1)+1/(sqrt(-3*x^2-2*x+1))).at n=11A246437
- Start with 83; if even, divide by 2; if odd, add next three primes: Orbit of 83 under iterations of A174221, the "PrimeLatz" map.at n=11A293979
- a(n) = 2*1 + 4*3 + 6*5 + 8*7 + 10*9 + 12*11 + ... + (up to the n-th term).at n=42A319866
- a(n) = n * Sum_{d|n} sigma(d)^2 / d.at n=49A344042
- Numbers with two or more distinct prime factors such that the number and all its prime factors fall on a single straight line when they are plotted on a square spiral.at n=37A346294
- G.f. satisfies A(x) = 1/(1-x) + x^3*(1-x)*A(x)^5.at n=12A364597