13688
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 26
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 27000
- Proper Divisor Sum (Aliquot Sum)
- 13312
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6496
- Möbius Function
- 0
- Radical
- 3422
- 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
- no
- 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
- yes
- Odd
- no
Appears in sequences
- Expansion of (theta_3(z)*theta_3(11z) + theta_2(z)*theta_2(11z))^4.at n=18A028612
- Numbers k such that tau(k) - tau(k+1) = 1.at n=19A068208
- Engel expansion of sinh(1/2).at n=29A068379
- Triangle T(n,k), read by rows, given by A000290 DELTA [1, 2, 6, 5, 11, 8, 16, 11, 21, 14, 26, 17, 31, 20, 36, ...] where DELTA is the operator defined in A084938.at n=18A088969
- Solutions to A096509[x]=6; number of prime-powers [including primes] in the neighborhood of x with Ceiling[Log[x]] radius equals 6.at n=5A096517
- a(n) = 9*n^2-1.at n=38A136016
- a(n) = 4*(3*n+1)*(3*n+2).at n=19A144410
- Nonsquarefree numbers such that n-1 is prime and n+1 is square.at n=27A146980
- a(0)=3; a(n) = n^2 + a(n-1) for n>0.at n=34A153057
- Expansion of g.f.: Product_{k>=1} 1+k*x^k/(1-x^k)^2.at n=15A163318
- Numbers such that the two adjacent integers are a perfect square and a prime.at n=42A163492
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 902", based on the 5-celled von Neumann neighborhood.at n=39A273760
- After a(0)=0, numbers n such that (A002828(1+n) = 1) and (A002828(4+n) = 4).at n=44A278491
- Numbers between a power and a prime.at n=47A329582
- Numbers k such that k and k+1 have different (ordered) prime signatures and d_3(k) = d_3(k+1), where d_3 is A007425.at n=2A333057
- Triangle T(n,k), n>=1, 0 <= k <= A002620(n-1), read by rows, where T(n,k) is the number of self-avoiding paths of length 2*(n+k) along the edges of a grid with n X n square cells, which do not pass above the diagonal, start at the lower left corner and finish at the upper right corner.at n=22A340043
- Numbers k such that k and k+1 are both terms of A365886.at n=42A365887