13394
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
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 20748
- Proper Divisor Sum (Aliquot Sum)
- 7354
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6480
- Möbius Function
- -1
- Radical
- 13394
- 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
- 94
- 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
- Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted then there are a pair of central terms both equal to 9.at n=22A031422
- Number of series-reduced dyslexic identity planted planar trees with n leaves of 2 colors.at n=7A032105
- Number of ways to partition 2n into distinct positive integers.at n=31A035294
- Numerators of continued fraction convergents to sqrt(769).at n=8A042482
- Number of ways to partition 4*n+2 into distinct positive integers.at n=15A078407
- Numbers k such that 5*10^k + 4*R_k - 3 is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=16A103013
- Even values of the PartitionsQ function A000009.at n=49A118303
- Triangle T, read by rows, where the n-th diagonal of T equals the BINOMIAL transform of the (n-1)-th diagonal of T^2 for n>=1, with the zeroth diagonal set to all 1's and where T^2 denotes the matrix square of T.at n=30A141712
- Column 2 of triangle A141712.at n=5A141714
- Twice 12-gonal numbers: a(n) = 2*n*(5*n-4).at n=37A152965
- n^2 + {1,3,7} are primes.at n=37A182238
- Number of partitions p of n such that if h = min(p), then h is an (h,1)-separator of p; see Comments.at n=51A239497
- Index of the n-th zero in the first occurrence of a string of exactly n zeros in the decimal expansion of Pi.at n=3A256109
- Numbers k such that 7*R_(k+2) - 6*10^k is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=21A257027
- a(n) is the smallest nonnegative k such that there is no 3 X 3 matrix with entries in {1,...,n} whose determinant is k.at n=20A262719
- a(n) = Sum_{k=1..n} prime(k)^2*floor(n/prime(k)) .at n=50A280385
- Number of partitions of n such that each part is no more than 3 more than the sum of all smaller parts.at n=35A286929
- a(n) = (n^2 + 1) * (2*n - 1).at n=18A290631