13065
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 15
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 22848
- Proper Divisor Sum (Aliquot Sum)
- 9783
- 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
- 1
- Radical
- 13065
- 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
- no
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 50
- 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
- a(n) = floor( n*(n-1)*(n-2)/22 ).at n=67A011904
- a(n) = n*(29*n + 1)/2.at n=30A022287
- a(n) = (d(n)-r(n))/2, where d = A026049 and r is the periodic sequence with fundamental period (1,0,0,1).at n=38A026050
- (d(n)-r(n))/2, where d = A008778 and r is the periodic sequence with fundamental period (1,1,0,1).at n=50A026052
- Numbers k such that k^2 is palindromic in base 8.at n=41A029805
- a(n) = 5*a(n-1) + 14*a(n-2), a(0)=1, a(1)=5.at n=5A053573
- McKay-Thompson series of class 15A for Monster.at n=16A058508
- Numbers k that divide 2^(k+3) - 1.at n=44A069927
- Number of primes of the form 7k+2 less than 10^n.at n=5A091121
- McKay-Thompson series of class 15A for the Monster group with a(0) = 1.at n=16A134783
- McKay-Thompson series of class 15A for the Monster group with a(0) = 4.at n=16A153765
- a(n) = ((2^b-1)/phi(n))*Sum_{d|n} Moebius(n/d)*d^(b-1) for b = 4.at n=28A160892
- G.f.: 1/(1 - x/(1 - x^3/(1 - x^4/(1 - x^7/(1 - x^11/(1 - x^18/(1 -...- x^Lucas(n)/(1 -...)))))))), a continued fraction.at n=25A206742
- -3-Knödel numbers.at n=25A225507
- Denominator of (1/3)*n*(n + 2)/((1 + 2*n)*(3 + 2*n)).at n=32A300295
- Numerator of variance of first n primes.at n=17A301275
- Number of parts in all partitions of n with largest multiplicity eight.at n=28A320378
- Number of vertices formed in a square by straight line segments when connecting the n+1 points along each edge that divide it into n equal parts to the n+1 points on the edge on the opposite side of the square.at n=9A355839