13638
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
- 8
- Divisor Sum
- 27288
- Proper Divisor Sum (Aliquot Sum)
- 13650
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 4544
- Möbius Function
- -1
- Radical
- 13638
- 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
- 138
- 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 that are the sum of 8 nonzero 8th powers.at n=19A003386
- Apply partial sum operator 4 times to binary rooted tree numbers.at n=12A014171
- Number of compositions of n such that the greatest part occurs with even multiplicity.at n=16A105204
- Triangle related to the o.g.f.s. of the right-hand columns of A028421 (E(x,m=2,n)).at n=25A163937
- Number of partitions of n, where the difference between the number of odd parts and the number of even parts is 10.at n=45A240019
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 485", based on the 5-celled von Neumann neighborhood.at n=26A272504
- Number of n X 6 0..1 arrays with no element equal to more than one of its horizontal and vertical neighbors, with the exception of exactly one element, and with new values introduced in order 0 sequentially upwards.at n=12A280438
- Numbers k such that (728*10^k - 71)/9 is prime.at n=20A293398
- Expansion of Product_{k>0} (1 + k*(k+1)/2 * x^(k*(k+1)/2)).at n=50A319256
- Expansion of Sum_{k>=1} (-1 + Product_{j>=1} (1 + x^(k*j))/(1 - x^(k*j))).at n=21A320942
- Number T(n,k) of colored integer partitions of n using all colors of a k-set such that a color pattern for part i has i distinct colors in increasing order; triangle T(n,k), n>=0, 0<=k<=n, read by rows.at n=42A327117
- 2*a(n) is the first of 5 consecutive even numbers that are sums of divisors, i.e., terms of A000203.at n=41A342560
- Matula-Goebel tree number of tree n with a new leaf added below each existing vertex.at n=45A348067