12986
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 26
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 20064
- Proper Divisor Sum (Aliquot Sum)
- 7078
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 6300
- Möbius Function
- -1
- Radical
- 12986
- Omega Function (Ω)
- 3
- 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
- 138
- 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
- Cubes written backwards.at n=40A004165
- Solution to the Dancing School Problem with 4 girls and n+4 boys: f(4,n).at n=11A079909
- a(n) = 7*n^2 + n.at n=43A092277
- Odd cubes written backwards and sorted.at n=11A107314
- Number of base 24 n-digit numbers with adjacent digits differing by two or less.at n=5A126411
- Number of 1-sided strip polycairos with n cells.at n=10A151535
- Number of (w,x,y,z) with all terms in {1,...,n} and w+x<=2y+2z.at n=11A212563
- Smallest k such that A002522(k) and A002522(k+2n) are successive primes of the form m^2+1.at n=34A245463
- Numbers n such that the sum of the triangular numbers T(n) and T(n+1) is equal to a heptagonal number H(m) for some m.at n=4A251927
- Expansion of a q-series used by Ramanujan in his Lost Notebook.at n=29A279715
- Sphenic numbers k such that none of k-2, k-1, k+1 and k+2 is squarefree.at n=39A362561
- E.g.f. A(x) satisfies A(x) = exp(x + x^4/24 * A'''(x)).at n=7A386532