15575
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 22320
- Proper Divisor Sum (Aliquot Sum)
- 6745
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10560
- Möbius Function
- 0
- Radical
- 3115
- 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
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 71
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) = (2*n+1) * (4*n-1).at n=44A033566
- Denominators of continued fraction convergents to sqrt(621).at n=7A042193
- Length of A001388(n).at n=32A046639
- Chebyshev polynomials S(n,25) with Diophantine property.at n=3A097780
- a(n) = n*(n^2 + 3*n + 5)/3.at n=35A145069
- a(n) = 25*n^2 - 2*n.at n=24A154376
- Partial sums of the tricapped prism numbers A005920.at n=13A187673
- a(2) = 1, then (p-1)*(p-4)/2, with p = prime(n), n > 2.at n=39A200050
- Semiperimeters s of primitive Pythagorean triples (a, b, c) where a, b, c and s are not squarefree.at n=30A237620
- Number of compositions of n such that the first part is 1 and the second differences of the parts are in {-10,...,10}.at n=16A239560
- a(n) = n^3 - 2*n.at n=25A242135
- Expansion of x*(1 - 2*x + x^2 + 7*x^3 - x^4)/((1 - x)^4*(1 + x)^3).at n=50A292551
- Number of strict multiset partitions of multiset partitions of integer partitions of n.at n=11A330453
- Numbers X such that X^2 + Y^2 = 5^(2*k) + 1 and X > Y > 0 and k is the quintal digit length of X-1.at n=10A369769
- Number of tripling steps to reach 1 in the 3x+1 (Collatz) problem starting with the n-th Mersenne prime.at n=17A390817