13528
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
- 2
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 27000
- Proper Divisor Sum (Aliquot Sum)
- 13472
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6336
- Möbius Function
- 0
- Radical
- 3382
- Omega Function (Ω)
- 5
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 138
- 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
- a(n) = floor(n(n+2)(2n+1)/8).at n=37A002717
- Number of recursive calls needed to compute the n-th Fibonacci number F(n), starting with F(1) = F(2) = 1.at n=19A019274
- dot_product(n,n-1,...2,1)*(7,8,...,n,1,2,3,4,5,6).at n=31A026066
- Global ranks of terms of A057122: tells which terms of A014486 form rooted plane binary trees also when interpreted as codes for ordinary rooted planar trees.at n=39A057123
- Radius of inscribed circle within primitive Pythagorean triangles having legs that add up to a square, sorted on hypotenuse.at n=40A089551
- 30*a(n) is the gap between sexy prime triples in the n-th sexy prime triple triple whose initial term is 17.at n=12A090891
- Numbers k such that k!*2^k - 1 is prime.at n=19A091415
- Partial sums of repeated Fibonacci sequence.at n=37A094707
- a(n) is the smallest positive d such that the n-th prime is the smallest prime p for which p+d is also prime.at n=35A101042
- A101042 sorted. There exists a prime p for which a(n) is the smallest positive d such that p is the smallest prime where p+d is also prime.at n=33A101043
- Even numbers k such that if a person is born in year k and lives not more than 100 years, then he never celebrates his prime birthday on a prime year.at n=11A124658
- Number of norep emirps less than 10^n.at n=7A131593
- a(n) = (4*n^3 + 11*n^2 + 9*n + 2)/2.at n=18A135712
- Length of the n-th term in the modified Look and Say sequence A110393.at n=35A179999
- Number of (w,x,y,z) with all terms in {1,...,n} and 2w=x+y+z.at n=32A212068
- a(n) = Fibonacci(p) mod p^2, where p = prime(n).at n=37A236395
- Number of (n+1) X (3+1) 0..2 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=4A253490
- T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with every 2X2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=25A253495
- Number of (5+1) X (n+1) 0..2 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=2A253499
- Numbers k satisfying |k + 1 - 2F| <= 1 for some positive Fibonacci number F.at n=52A256007