12643
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 12960
- Proper Divisor Sum (Aliquot Sum)
- 317
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 12328
- Möbius Function
- 1
- Radical
- 12643
- 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
- 156
- 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
- Number of partitions in parts not of the form 15k, 15k+1 or 15k-1. Also number of partitions with no part of size 1 and differences between parts at distance 6 are greater than 1.at n=45A035955
- Numbers m such that the positive values of m - A002110(k) are all primes (k > 0).at n=35A068372
- Centered 14-gonal numbers.at n=42A069127
- Take pairs (x,y) with Sum_{j = x..y} j = concatenation of x and y. Sort pairs on y then x. This sequence gives x of each pair.at n=32A070152
- Numerators of Apéry-style convergents to 4/11 log 2.at n=3A114497
- Number of 4-almost primes f such that 2^n < f <= 2^(n+1).at n=16A120035
- Record values in A180076.at n=36A180080
- Numbers k such that the sum of digits^3 of k equals Sum_{d|k, 1<d<k} d.at n=4A202279
- Number of compositions of n with at most one 1.at n=19A206268
- Numbers n such that sum of cubes of digits of n equals the sum of prime divisors of n.at n=5A217531
- Number of length n 1..(3+2) arrays with no leading or trailing partial sum equal to a prime.at n=10A254199
- Numbers whose arithmetic derivative is equal to the sum of some fixed power of their digits.at n=8A269719
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 605", based on the 5-celled von Neumann neighborhood.at n=22A273177
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 870", based on the 5-celled von Neumann neighborhood.at n=34A273705
- Numbers n such that A003145(n) = floor(alpha^2*n)+1, where alpha = 1.839... is the positive real zero of x^3-x^2-x-1.at n=37A278352
- a(n) = -n^3 + 70*n^2 - 939*n + 2393.at n=41A279538
- Triangle read by rows: T(n,k) is the number of disconnected permutation graphs on n vertices with domination number k, with 2 <= k <= n.at n=30A320579
- Composite numbers k such that k-1 divides 2^k-2.at n=18A330382
- a(0) = 0, a(1) = 1. For n >= 2, a(n) = a(n-1)/(n-1) if n-1 divides a(n-1); otherwise, a(n) = a(n-1) + a(n-2).at n=39A343376
- Maximum coefficient of (1 - x) * (1 - x^3) * (1 - x^6) * ... * (1 - x^(n*(n+1)/2)).at n=46A369984