12108
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 12
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 28280
- Proper Divisor Sum (Aliquot Sum)
- 16172
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4032
- Möbius Function
- 0
- Radical
- 6054
- 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
- yes
- Harshad Number
- yes
- Narcissistic Number
- no
- Collatz Steps
- 68
- 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
- From rook polynomials.at n=10A001925
- E.g.f.: Expansion of log(1+log(1+x)^2) = 2*x^2/2! -6*x^3/3! +10*x^4/4! -...at n=8A009325
- a(n) is the concatenation of n and 9n.at n=11A009474
- "CHJ" (necklace, identity, labeled) transform of 3,3,3,3...at n=4A032330
- Base-7 palindromes that start with 5.at n=18A043019
- Width of the bit-masks A068221 & A068222 (number of digits in A068223 & A068224).at n=12A068739
- Trisection of A007294.at n=35A073472
- Interprimes which are of the form s*prime, s=12.at n=30A075287
- Average of twin-prime pairs for pairs that are expressible as the sum of two triangular numbers.at n=24A117313
- Triangle read by rows: T(n,k) (n >= 1, 1 <= k <= n) = largest permanent of any n X n (0,1) matrix with k 1's in each row and column.at n=41A133644
- Friedman numbers n such that n+1 is also a Friedman number.at n=23A195420
- A001251(n)/2.at n=7A213452
- Numbers k such that phi(k-6) = phi(k) = phi(k+6).at n=17A217006
- Number of conjugacy classes in Chevalley group G_2(q) as q runs through the prime powers.at n=38A225929
- Number of n-step self-avoiding walks on cubic lattice ending at point with x = k.at n=40A227338
- Number of length n+4 0..7 arrays with every five consecutive terms having four times some element equal to the sum of the remaining four.at n=4A249655
- Number of length 5+4 0..n arrays with every five consecutive terms having four times some element equal to the sum of the remaining four.at n=6A249661
- Number of length 3+2 0..n arrays with the sum of second differences squared multiplied by some arrangement of +-1 equal to zero.at n=14A250322
- Number of (n+2) X (7+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 1 and no antidiagonal sum 2 and no row sum 0 and no column sum 3.at n=37A255800
- Triangle read by rows: T(n,k) is the number of compositions of n having degree of asymmetry equal to k (n>=0; 0<=k<=n/3).at n=53A275433