12209
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 12660
- Proper Divisor Sum (Aliquot Sum)
- 451
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 11760
- Möbius Function
- 1
- Radical
- 12209
- 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
- 112
- 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
- Rhombic dodecahedral numbers: a(n) = n^4 - (n - 1)^4.at n=14A005917
- Pseudoprimes to base 6.at n=31A005937
- a(n) = n*(n^2 + 1)/2.at n=29A006003
- Pseudoprimes to base 33.at n=34A020161
- Pseudoprimes to base 51.at n=38A020179
- Pseudoprimes to base 70.at n=38A020198
- Strong pseudoprimes to base 51.at n=11A020277
- Strong pseudoprimes to base 70.at n=12A020296
- Numbers k such that the continued fraction for sqrt(k) has period 43.at n=33A020382
- a(n) = n*(29*n + 1)/2.at n=29A022287
- T(n, 2*n-4), T given by A027960.at n=21A027966
- Denominators of continued fraction convergents to sqrt(189).at n=9A041351
- Number of open positions in the game Fair Share and Varied Pairs starting with n tokens.at n=34A060463
- Sum of the elements in any transversal of a prime(n) X prime(n) array containing the numbers from 1 to prime(n)^2 in standard order.at n=9A066886
- a(n) = least natural number k such that f(k) begins a maximal zigzag of length n in the prime gaps function f(x) = p(x+1)-p(x), where p(x) denotes the x-th prime. (Cf. A066485.)at n=11A066918
- Expansion of (1+x^4*C^2)*C^3, where C = (1-(1-4*x)^(1/2))/(2*x) is g.f. for Catalan numbers, A000108.at n=8A071748
- Row sums of triangle A074135.at n=28A074132
- Sum of terms in each group in A074147.at n=28A074149
- Greedy frac multiples of Pi^2/6: a(1)=1, Sum_{n>=1} frac(a(n)*x) = 1 at x = Pi^2/6.at n=11A079937
- Denominators of the convergents to the continued fraction of Pi^2/6.at n=10A080017