15834
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 32
- Divisor Sum
- 40320
- Proper Divisor Sum (Aliquot Sum)
- 24486
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4032
- Möbius Function
- -1
- Radical
- 15834
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 5
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
- 146
- 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
- yes
- Odd
- no
Appears in sequences
- a(n) = n*(n+1)*(4*n+5)/6.at n=28A016061
- Expansion of (Product_{j>=1} (1-(-x)^j) - 1)^13 in powers of x.at n=12A047638
- a(n) = A028321(n)/2.at n=28A051473
- Treated as strings, phi(n) is a substring of sigma(n).at n=25A074452
- Squarefree balanced numbers (i.e., squarefree members of A020492).at n=32A078557
- a(n) = rad(n*(n+1)*(n+2)*(n+3)).at n=25A078638
- Number of positive numbers m such that A073642(m) = n.at n=57A087135
- Numbers n such that the denominator of the 2n-th Bernoulli number is divisible by n but sum_{d|n} sigma(d)/phi(d) is not an integer.at n=11A099008
- Numbers n such that n divides the denominator of 2n-th Bernoulli number.at n=34A106741
- Expansion of (1 + x)/(1 + x + 2x^2).at n=29A110512
- a(n) = binomial(n,4) - binomial(floor(n/2),4) - binomial(ceiling(n/2),4).at n=27A111385
- Row sums of triangle A120072 (numerator triangle for H atom spectrum).at n=27A120074
- Numbers such that sigma(n)^2 is divisible by UnitarySigma(n)*UnitaryPhi(n).at n=41A121556
- Numbers k such that the central binomial coefficient C(2k,k) is divisible by k^2.at n=30A121943
- Numbers such that Sigma(m)*UnitarySigma(m)= k*UnitaryPhi(m)^2, for some integer k.at n=37A122839
- Numbers m such that UnitarySigma(m)^2 = k*Sigma(m)*UnitaryPhi(m), for some integer k.at n=37A123041
- Table of Encoded Bell Multisets using A064553 (cf. A129305).at n=23A130274
- 4-Stirling numbers of the second kind.at n=41A143496
- Row sums of triangle A144825.at n=28A144826
- 7 times pentagonal numbers: a(n) = 7*n*(3*n-1)/2.at n=39A152744