13755
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
- 3
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 25344
- Proper Divisor Sum (Aliquot Sum)
- 11589
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6240
- Möbius Function
- 1
- Radical
- 13755
- 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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 182
- 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
- Alkane (or paraffin) numbers l(7,n).at n=26A005994
- Expansion of Product_{k>=1} (1 - x^k)^15.at n=13A010822
- a(n) = Sum_{i=1..floor((n+1)/4)} a(2*i-1) * a(n-2*i+1), with a(1)=a(2)=1 and a(3)=5.at n=14A024729
- a(n) = dot_product(1,2,...,n)*(3,4,...,n,1,2).at n=32A026037
- Numbers k that divide the (right) concatenation of all numbers <= k written in base 7 (most significant digit on left).at n=50A029452
- Multiplicity of highest weight (or singular) vectors associated with character chi_10 of Monster module.at n=41A034398
- Composite numbers k such that digits in k and in juxtaposition of prime factors of k are the same (apart from multiplicity).at n=34A035141
- Numbers with exactly 4 distinct palindromic prime factors.at n=32A046402
- Odd numbers with exactly 4 distinct palindromic prime factors.at n=2A046406
- a(n) = n*(n+1)*(2*n^2+1)/6.at n=14A071238
- Gives an LCD representation of n.at n=32A071843
- Smallest multiple of n using all the digits of all its divisors (a permutation of the concatenation of its divisors), or 0 if no such number exists.at n=34A077351
- Minimal k > n such that (4k+3n)(4n+3k) is a square.at n=34A083752
- Numbers k for which nontrivial positive magic squares of exactly 9 different orders with magic sum k exist. For a definition of nontrivial positive magic squares, see A125005.at n=27A125016
- Number of up/down (or down/up) compositions of n into distinct parts.at n=35A129838
- a(n) = 529*n + 1.at n=25A158368
- a(n) = 26*n^2 + 1.at n=23A158549
- Triangle read by rows, T(n,k) = T(n-1,k-1) + k*T(n-1,k) + (k+1)*T(n-1,k+1), T(0,0) = 1, n >= 0, k >= 0.at n=50A217537
- Number of nondecreasing -n..n vectors of length 3 whose dot product with some lexicographically greater than or equal to nondecreasing -n..n vector equals 3.at n=23A226424
- Numbers m, such that the smallest prime factor of 1+78557*2^m doesn't belong to the covering set {3, 5, 7, 13, 19, 37, 73}.at n=39A258095