12389
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 13356
- Proper Divisor Sum (Aliquot Sum)
- 967
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 11424
- Möbius Function
- 1
- Radical
- 12389
- 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
- 187
- 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
- no
- Odd
- yes
Appears in sequences
- Numbers n such that n divides the (right) concatenation of all numbers <= n written in base 19 (most significant digit on right).at n=27A029512
- Numbers k such that the continued fraction for sqrt(k) has odd period and if the last term of the periodic part is deleted the two central terms are both 13.at n=12A031601
- Number of binary rooted trees with n nodes and height exactly 6.at n=21A036595
- Smallest number m with nonzero digits such that A046810(m)=n.at n=32A046813
- a(n) is the least integer that has exactly n anagrams that are primes.at n=32A046890
- a(n) is the least number with exactly n permutations of digits that are primes.at n=32A046893
- a(n) = (2*n-1)*(5*n^2-5*n+6)/6.at n=19A063489
- Numerators of partial sums of reciprocals of lcm(1..n) = A003418(n).at n=10A064857
- An accelerator sequence for Catalan's constant.at n=16A094648
- Trace sequence of a path graph plus loop.at n=16A096975
- a(0) = 0, a(1) = 1, a(2) = 1, a(3) = 2, a(4) = 4, for n>3: a(n+1) = SORT[a(n) + a(n-1) + a(n-2) + a(n-3)], where SORT places digits in ascending order and deletes 0's.at n=31A108564
- Numbers n such that p(5n) is prime, where p(n) is the number of partitions of n.at n=30A114166
- Let M(n) be the n X n matrix m(i,j)=min(i,j) for 1<=i,j<=n then a(n) is the trace of M(n)^(-8).at n=2A114360
- Number of monomials in discriminant of symbolic Tschirnhausen polynomial of degree n (with three zero coefficients at x^(n-1), x^(n-2) and x^(n-3)).at n=10A138802
- a(n) = 3*A022004(n) + 8.at n=35A163635
- Rectangular array read by antidiagonals: row q has generating function F_q(x) = sum_{r=0,...,q-1} ((q-r)*(-1)^r*binomial(2*q-r,r)*x^r) / sum_{s=0,...,q} ((-1)^s*binomial(2*q-s,s)*x^s), where q=1,2,....at n=63A185095
- Sequence read from antidiagonals of rectangular array with entry in row n and column q given by T(n,q) = 2^(2*n)*(Sum_{j=1..n+1} (cos(j*Pi/(2*q+1)))^(2*n)), n >= 0, q >= 1.at n=57A186740
- One half of total number of round trips, each of length 2n, on the graph P_6 (o-o-o-o-o-o).at n=8A198636
- Number of (n+2)X(n+2) 0..1 arrays with every 3X3 subblock sum of the two sums of the diagonal and antidiagonal minus the two minimums of the central column and central row nondecreasing horizontally, vertically and ne-to-sw antidiagonally.at n=11A254899
- G.f. A(x) = Sum_{n=-oo..+oo} x^n * (1 + x^n)^(2*n).at n=57A260147