13242
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
- 3
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 26496
- Proper Divisor Sum (Aliquot Sum)
- 13254
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 4412
- Möbius Function
- -1
- Radical
- 13242
- 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
- 45
- 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
- a(n) = round(n*phi^16), where phi is the golden ratio, A001622.at n=6A004951
- a(n) = ceiling(n*phi^16), where phi is the golden ratio, A001622.at n=6A004971
- Coordination sequence for squashed {D_5}* lattice, perhaps the smallest example of a "non-superficial" lattice.at n=8A010024
- Magic numbers: atoms with full shells containing any of these numbers of electrons are considered electronically stable.at n=40A018227
- Rounded volume of a regular dodecahedron with edge length n.at n=12A071401
- Number of n X 3 1..2 arrays containing at least one of each value, all equal values connected, rows considered as a single number in nondecreasing order, and columns considered as a single number in nonincreasing order.at n=40A166830
- a(n) is the number of digits in the decimal representation of the smallest power of n that contains nine consecutive identical digits.at n=13A217184
- Numbers such that Liouville's function (A002819) and the little omega analog to Liouville's function (A174863) are equal.at n=47A224987
- Number of tilings of a 6 X n rectangle with right trominoes.at n=10A351323
- Even numbers 2m such that A352612(2m) = A103131(2m).at n=30A352587
- a(n) is the number of reducible monic quartic polynomials (x^4 + r*x^3 + s*x^2 + t*x + u) with integer coefficients bounded by naïve height n (abs(r), abs(s), abs(t), abs(u) <= n).at n=7A358399
- Triangle read by rows: T(n,k) is the total number of bubbles of size k found in linear chord diagrams on 2n vertices.at n=48A367000