13870
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 26640
- Proper Divisor Sum (Aliquot Sum)
- 12770
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5184
- Möbius Function
- 1
- Radical
- 13870
- 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
- 151
- 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
- Number of partitions of n with equal number of parts congruent to each of 0 and 3 (mod 4).at n=44A035542
- Base 9 digits are, in order, the first n terms of the periodic sequence with initial period 2,1,0.at n=4A037526
- Number of symmetric nonnegative integer 7 X 7 matrices with sum of elements equal to 4*n, under action of dihedral group D_4.at n=9A054497
- Consider the sequence b(k) such that b(k) and sigma(b(k)) end with the same digit in base 10. Sequence gives values of b(k) such that b(k)/k = 10.at n=28A065255
- a(n) = Sum_{i=1..n} binomial(4*i,2*i).at n=3A066797
- Number of ways to place zero or more nonadjacent 1,0 2,0 2,1 2,2 3,0 4,0 polyhexes in any orientation on a planar nXnXn triangular grid.at n=6A155254
- Row 4 of table A162424.at n=23A162427
- a(n) = (4*n^3 + n^2 - 3*n)/2.at n=19A172073
- a(n) = n*(n+1)*(11*n +10)/6.at n=19A254407
- a(n) = cpg(n, 3) + cpg(n, 4) + ... + cpg(n, n) where cpg(n, m) is the m-th n-th-order centered polygonal number.at n=17A257051
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 433", based on the 5-celled von Neumann neighborhood.at n=26A272147
- E.g.f.: exp(-x * exp(x)).at n=11A292952
- Number of integer partitions of n such that every set of distinct parts has a different sum.at n=45A325862
- Primitive terms of A359565: terms of A359565 with no proper divisor in A359565.at n=33A359566
- Number of unlabeled connected multigraphs with circuit rank n and degree >= 3 at each node, loops allowed.at n=5A360864
- Expansion of 1/(1 - 4*x^2/(1-x))^(5/2).at n=9A377215