13797
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 27
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 23680
- Proper Divisor Sum (Aliquot Sum)
- 9883
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7776
- Möbius Function
- 0
- Radical
- 1533
- Omega Function (Ω)
- 5
- 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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 151
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- Number of n-bead necklaces with beads of 2 colors and primitive period n, when turning over is not allowed but the two colors can be interchanged.at n=19A000048
- Lerch's function q_2(n) = (2^{phi(t)} - 1)/t where t = 2*n - 1.at n=9A001226
- Divisors of 2^18 - 1.at n=27A003528
- a(n) = floor(2^(n-1)/n).at n=18A006788
- Fermat quotients: (2^(p-1)-1)/p, where p=prime(n).at n=6A007663
- Array (a frieze pattern) defined by a(n,k) = (a(n-1,k)*a(n-1,k+1) - 1) / a(n-2,k+1), read by antidiagonals.at n=50A007754
- Least k such that (2*p_n)*k + 1 | Mersenne(p_n), p_n = n-th prime, n >= 2.at n=6A016048
- Fibonacci sequence beginning 1, 22.at n=15A022392
- Number of Hamiltonian cycles in the directed graph with 2n nodes {0..2n-1} and edges from each i to 2i (mod 2n) and to 2i+1 (mod 2n).at n=18A027362
- Number of different determinants of n X n persymmetric matrices with entries {-1,0,+1}.at n=8A034921
- Maximum cycle length in differentiation digraph for n-bit binary sequences.at n=26A038553
- Number of binary Lyndon words with an even number of 1's.at n=18A051841
- Number of binary vectors (x_1,...x_n) satisfying Sum_{i=1..n} i*x_i = 3 (mod n+1) = size of Varshamov-Tenengolts code VT_3(n).at n=18A054200
- Nearest integer to 2^(n-1)/n.at n=18A054650
- Number of n-bead necklace structures using exactly two different colored beads.at n=18A056295
- Number of primitive (period n) n-bead necklace structures using exactly two different colored beads.at n=18A056303
- Ultra-useful primes: smallest k such that 2^(2^n) - k is prime.at n=13A058220
- Row 5 of A007754.at n=4A058796
- Number of orbits of length n under a map whose periodic points are counted by A027306.at n=18A060172
- Number of orbits of length n in a map whose periodic points come from A059991.at n=18A060481