13443
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
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 17928
- Proper Divisor Sum (Aliquot Sum)
- 4485
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8960
- Möbius Function
- 1
- Radical
- 13443
- 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
- 45
- 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
- Sum of digits in n-th term of A022482.at n=29A022487
- Expansion of Product_{m>=1} (1+x^m)^15.at n=5A022580
- a(n) = s(1)s(n) + s(2)s(n-1) + ... + s(k)s(n+1-k), where k = [ (n+1)/2 ], s = (composite numbers).at n=37A024588
- s(1)s(n) + s(2)s(n-1) + ... + s(k)s(n-k+1), where k = [ n/2 ], s = (composite numbers).at n=36A025102
- Number of rooted non-separable Eulerian planar maps with n edges.at n=11A069728
- Least k such that the distance from k^2 to closest prime = n or zero if no k exists.at n=49A079666
- a(n+1) = floor(a(n) * Sum_{k=0..n} 1/a(k)^s), where s = Sum_{k>=0} 1/a(k)^s and a(0)=1; s = 2.260568736857767...at n=13A080135
- Numbers n such that (n+j) mod (2+j) = 1 for j from 0 to 6 and (n+7) mod 9 <> 1.at n=10A096025
- Irregular array where the n-th row are the divisors, not occurring earlier in the sequence, of the sum of the terms in all previous rows. a(1)=3.at n=43A120577
- Numbers k for which 5*k-4, 5*k-2, 5*k+2, and 5*k+4 are primes.at n=27A178082
- a(n) = floor((-1 + 2^n)/(1 + 2*n)).at n=18A191630
- a(n) = floor((1 + 2^n)/(1 + 2*n)).at n=18A191633
- G.f.: A(x) = Sum_{n>=0} x^(n^2) / Product_{k=1..n} (1 - x^k)^n.at n=24A193197
- Number of partitions of n with difference 10 between the number of odd parts and the number of even parts, both counted without multiplicity.at n=35A242701
- Number of preferential arrangements of n labeled elements when at least k=5 elements per rank are required.at n=14A245790
- Coefficients of e.g.f. for numbers of graded interval orders.at n=6A268215
- Number of square plane partitions of n with strictly decreasing rows and columns.at n=52A323530
- a(n) = Sum_{k=1..floor(n/2)} k * (n-k) * floor((n-k)/k).at n=37A339804
- a(n) = Sum_{k=0..floor(n/2)} binomial(3*n+k-1,k) * binomial(3*n+k,n-2*k).at n=5A379086
- Square array A(n,k), n >= 0, k >= 0, read by antidiagonals downwards, where column k is the expansion of e.g.f. B(x)^k, where B(x) is the e.g.f. of A384809.at n=41A384811