12087
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 18720
- Proper Divisor Sum (Aliquot Sum)
- 6633
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 7488
- Möbius Function
- 0
- Radical
- 4029
- Omega Function (Ω)
- 4
- 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
- 125
- 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
- Convolution of odd numbers and A000201.at n=27A023658
- Expansion of g.f. (1-x^2)/(1-x-2*x^2+x^3).at n=17A028495
- Row sums of triangle A060556.at n=8A060557
- Positions of sevens (ground states) in A084451.at n=21A084449
- Numbers k such that the digits of sigma(k) are a permutation of those of k, in base 10.at n=18A115920
- The sums of pairs of adjacent terms are the odd palindromic primes in ascending order.at n=38A181881
- Let i be in {1,2,3} and let r >= 0 be an integer. Let p = {p_1, p_2, p_3} = {-2,0,1}, n = 2*r + p_i and define a(-2)=0. Then, a(n) = a(2*r + p_i) gives the quantity of H_(7,3,0) tiles in a subdivided H_(7,i,r) tile after linear scaling by the factor x^r, where x = sqrt(2*cos(Pi/7)).at n=35A187067
- Numbers n that divide the sum of digits of 36^n.at n=36A220364
- T(n,k)=Number of length (n+k)X1 arrays of occupancy after each element moves up to +-k places including 0.at n=34A222345
- Number of (n+7)X1 arrays of occupancy after each element moves up to +-n places including 0.at n=1A222351
- The hyper-Wiener index of the zig-zag polyhex nanotube TUHC_6[2n,2] defined pictorially in Fig. 1 of the Eliasi et al. reference.at n=7A227704
- Indices of zeros in A269783.at n=43A269967
- Number of palindromic compositions of n with parts in {1,2,4,6,8,10,...}.at n=35A276055
- Numbers which are palindromic in their Elias delta code representation.at n=32A281380
- a(n) = Sum_{d|n} d^3*A000593(n/d).at n=21A288419
- Number of partitions p of n such that (number of numbers in p that have multiplicity 1) != (number of numbers in p having multiplicity > 1).at n=35A330147
- a(n) = Sum_{k=1..n} (binomial(n, k) * 3^k) (mod 4^k).at n=7A386662
- Expansion of (1/x) * Series_Reversion( x / (1 + x^3 / (1 - x)^2) ).at n=14A389249