15365
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 21120
- Proper Divisor Sum (Aliquot Sum)
- 5755
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 10512
- Möbius Function
- -1
- Radical
- 15365
- Omega Function (Ω)
- 3
- 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
- 40
- 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
- Numbers k such that sigma(k) = sigma(k+4).at n=20A015863
- 5-digit terms in the continued fraction for Pi.at n=7A048960
- Expansion of ( 1-x ) / ( 1-4*x-x^2+2*x^3 ).at n=7A052990
- Sixth column (r=5) of FS(3) staircase array A062745.at n=13A062749
- Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^4<x^4+y^4.at n=28A211652
- Coefficients of (x^(1/4)*d/dx)^n for n positive integer.at n=29A223534
- Table read by antidiagonals of numbers of form (2^n - 1)*2^(m+3) + 5 where n>=1, m>=1.at n=48A224701
- Number of standard Young tableaux with n cells such that the lengths of the first and the last row differ by 7.at n=4A244301
- Least number k such that (n!+k)/n and (n!-k)/n are both prime.at n=32A245697
- Number of length n arrays x(i), i=1..n with x(i) in i..i+4 and no value appearing more than 3 times.at n=5A250357
- T(n,k)=Number of length n arrays x(i), i=1..n with x(i) in i..i+k and no value appearing more than 3 times.at n=41A250361
- Number of length 6 arrays x(i), i=1..6 with x(i) in i..i+n and no value appearing more than 3 times.at n=3A250364
- Number of n-bit legal binary words with maximal set of 1s.at n=29A253412
- Growth series for affine Coxeter group B_5.at n=17A267168
- a(n) is the number of reducible monic quintic polynomials (x^5 + r*x^4 + s*x^3 + t*x^2 + u*x + v) with integer coefficients bounded by naïve height n (abs(r), abs(s), abs(t), abs(u), abs(v) <= n).at n=3A358400
- G.f. A(x) satisfies A(x) = 1 + x^3*(1+x)^2*A(x)^3.at n=17A366591
- Numbers k such that there is a smaller number m > 1 such that k*m equals the concatenation of digit-wise multiplication, keeping the leading digits of k when m has fewer digits.at n=39A392568