11445
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
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 21120
- Proper Divisor Sum (Aliquot Sum)
- 9675
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5184
- Möbius Function
- 1
- Radical
- 11445
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 4
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 29
- Smith Number
- no
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) = (4*n+1)*(4*n+5).at n=26A003185
- G.f.: 1/((1-x)*(1-x^2)*(1-x^3)^2*(1-x^4)*(1-x^5)).at n=46A003402
- a(n) = n*(13*n - 1)/2.at n=42A022270
- Expansion of 1/((1-6x)(1-8x)(1-9x)(1-10x)).at n=3A028210
- Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= (n-2)/3.at n=24A048018
- Number of nonempty subsets of {1,2,...,n} in which exactly 2/3 of the elements are <= (n-3)/3.at n=24A048029
- Numbers k that divide 2^(k+3) - 1.at n=41A069927
- Let f(1)=f(2)=1, f(k)=f(k-1)+f(k-2)+ (k (mod n)). Then f(k)=floor(r(n)*F(k))+g(k) where F(k) denotes the k-th Fibonacci number and g(k) a function becoming periodic. Sequence depends on r(n) which is the largest positive root of : a(3n-2)*X^2-a(3n-1)*X+a(3n)=0.at n=46A081420
- Numbers k such that 13*3^k + 2 is prime.at n=13A084125
- a(n) is the least odd composite number m such that nextprime(p*m) > p*nextprime(m) where p is the n-th prime.at n=13A117103
- Refines A075197(n): number of partitions of n balls of n colors. The refinement has shape A000041(n).at n=37A130273
- First trisection of A061037 (Balmer line series of the hydrogen atom).at n=35A142590
- Quintisection A061037(5*n+2).at n=21A165248
- a(n) = A061037(7*n+2).at n=15A165943
- a(n) = prime(n)^2-4.at n=27A166010
- -3-Knödel numbers.at n=24A225507
- Starting from a(1)=1, a(n) is the minimum integer greater than a(n-1) such that a(n)+a(n-1), a(n)*a(n-1)+1 and a(n)*a(n-1)-1 are all primes.at n=44A228590
- Number of (n+1)X(3+1) 0..1 arrays x(i,j) with row sums sum{j^3*x(i,j), j=1..3+1} nondecreasing, and column sums sum{i^3*x(i,j), i=1..n+1} nondecreasing.at n=4A232856
- Number of (n+1)X(5+1) 0..1 arrays x(i,j) with row sums sum{j^3*x(i,j), j=1..5+1} nondecreasing, and column sums sum{i^3*x(i,j), i=1..n+1} nondecreasing.at n=2A232858
- T(n,k)=Number of (n+1)X(k+1) 0..1 arrays x(i,j) with row sums sum{j^3*x(i,j), j=1..k+1} nondecreasing, and column sums sum{i^3*x(i,j), i=1..n+1} nondecreasing.at n=23A232860