12646
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
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 18972
- Proper Divisor Sum (Aliquot Sum)
- 6326
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6322
- Möbius Function
- 1
- Radical
- 12646
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- 156
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- Molien series of 4-dimensional representation of u.g.g.r. #9.at n=15A013977
- Molien series of 4-dimensional representation of u.g.g.r. #8.at n=30A013978
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 88 ones.at n=7A031856
- Sum of the first n safe primes.at n=27A066869
- Number of benzenoids with 22 hexagons, C_(2h) symmetry and containing 2n carbon atoms.at n=6A123105
- a(n) = prime(n^2) - n^2.at n=40A141129
- Symmetrical triangle sequence from polynomials: q(x,n)=(-1)^n*(Sum[(k + 1)^n*x^k/k, {k, 1, Infinity}] + Log[1 - x])*(x - 1)^n/x; p(x,n)=q(x,n)+x^n*q(1/x,n).at n=39A154989
- Symmetrical triangle sequence from polynomials: q(x,n)=(-1)^n*(Sum[(k + 1)^n*x^k/k, {k, 1, Infinity}] + Log[1 - x])*(x - 1)^n/x; p(x,n)=q(x,n)+x^n*q(1/x,n).at n=41A154989
- Triangle, read by rows, where row n equals the coefficients of y^k in R_{n-1}(y+y^2) for k=1..n where R_n(y) is the n-th row polynomial in y for n>1 with R_1(y)=y.at n=41A187005
- a(n) = (n^3 - 2*n^2 + 3*n + 2)/2.at n=30A189890
- a(n) = A193467(n)/n for n>=1.at n=5A193469
- Numbers n such that m + (sum of digits in base-3 representation of m) = n has exactly four solutions.at n=44A230856
- Number of (n+1)X(6+1) 0..1 arrays with every 2X2 subblock ne-sw antidiagonal difference unequal to its neighbors horizontally and nw+se diagonal sum unequal to its neighbors vertically.at n=8A253696
- Number of length 5 1..(n+2) arrays with no leading partial sum equal to a prime and no consecutive values equal.at n=8A255720
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 310", based on the 5-celled von Neumann neighborhood.at n=31A271198
- Sum of the fourth largest parts of the partitions of n into 9 squarefree parts.at n=52A326529
- Expansion of e.g.f. Sum_{k>=1} log(1 + log(1/(1 - x))^k) / k.at n=7A330498
- Indices of records in A307730.at n=32A348449
- Irregular triangle read by rows: T(n,k) is the coefficient of x^k in the domination polynomial of the n X n king graph (n>=1, A075561(n)<=k<=n^2).at n=44A378420