16212
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
- 2
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 43456
- Proper Divisor Sum (Aliquot Sum)
- 27244
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 4608
- Möbius Function
- 0
- Radical
- 8106
- Omega Function (Ω)
- 5
- Little Omega Function (ω)
- 4
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 115
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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) = 2*a(n-1) + a(n-2) - a(n-3), with a(0) = a(1) = 0, a(2) = 1.at n=14A006054
- Maximal length of rook tour on an n X n board.at n=28A006071
- 3-wave sequence starting with 1, 1, 1.at n=25A038196
- Numbers k such that k | sigma_8(k).at n=17A055712
- Number of cycles in range [A014137(n-1)..A014138(n-1)] of permutation A057505/A057506.at n=14A057507
- Pseudo-random numbers: a (very weak) pseudo-random number generator from the second edition of the C book.at n=8A061364
- Number of even cycles in range [A014137(n-1)..A014138(n-1)] of permutation A057505/A057506.at n=14A081150
- Number of even cycles in range [A014137(2n-1)..A014138(2n-1)] of permutation A057505/A057506.at n=7A081151
- First differences of A084449.at n=34A084465
- Numbers k such that 2^k - 1 is divisible by (k-1).at n=20A087965
- Slowest increasing sequence beginning with 1 whose digits satisfy the rule d*2.at n=11A102252
- Begin with 3, multiply each digit by 2, keeping the memory of the groupings of the preceding digits.at n=6A102254
- Numbers k such that 7*10^k + 2*R_k + 1 is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=13A103053
- Expansion of g.f.: 1/(1 - 2*x - x^2 + x^3).at n=12A106805
- Expansion of ( 1-x^3+x^4+x^5-x^8 ) / ( 1-2*x^3-x^6+x^9 ).at n=40A120771
- The Wiener index of a chain of n triangles (i.e., joined like VVV..VV; here V is a triangle!).at n=27A143941
- Expansion of g.f. 1 - 2*x*(-7 - 10*x + x^2)/(x - 1)^4.at n=14A152100
- Values of n such that n^a-+a are primes, a=5.at n=16A155021
- Partial sums of A023200.at n=39A172112
- Let i be in {1,2,3}, let r >= 0 be an integer and n=2*r+i-1. Then a(n)=a(2*r+i-1) gives the quantity of H_(7,1,0) tiles in a subdivided H_(7,i,r) tile after linear scaling by the factor x^r, where x=sqrt((2*cos(Pi/7))^2-1).at n=29A187068