16211
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 11
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 18480
- Proper Divisor Sum (Aliquot Sum)
- 2269
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 14112
- Möbius Function
- -1
- Radical
- 16211
- 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
- 71
- 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
- no
- Odd
- yes
Appears in sequences
- a(n) = prime(n) * Fibonacci(n).at n=13A064497
- Polynexus numbers of order 8.at n=6A088890
- Indices of primes in sequence defined by A(0) = 73, A(n) = 10*A(n-1) - 7 for n > 0.at n=13A101134
- Negative numbers written in a bits-of-Pi/primorial base system.at n=20A109839
- Number of degeneracies on the sets of N ordinary trees with p vertices.at n=8A120979
- 13 times pentagonal numbers: a(n) = 13*n*(3*n-1)/2.at n=29A153793
- Numbers k that divide 10^(k+1)-1.at n=40A175203
- Numbers k such that 2^(k+1) == 1 (mod k).at n=20A187787
- Composite numbers n such that b^(n+1) == 1 (mod n) for every b coprime to n.at n=11A208728
- A027642(6*n+6)/(sequence of period 2:repeat 42,210).at n=13A216639
- A027642(6*n+6)/(sequence of period 2:repeat 42,210).at n=27A216639
- Lucas pseudoprimes.at n=15A217120
- Numbers which are the roots of distinct not-previously-encountered side-trees ("tendrils") sprouting from the side of the infinite beanstalk (see A213730).at n=33A218612
- Numbers such that the sequence of all possible sums of divisors of n is increasing but not strictly so, the sums being ordered by their characteristic functions, seen as binary numbers (see example).at n=11A230492
- Number of (n+1) X (1+1) 0..1 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.at n=9A250576
- T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with nondecreasing max(x(i,j),x(i,j-1)) in the i direction and nondecreasing min(x(i,j),x(i-1,j)) in the j direction.at n=45A250583
- a(0)=0, a(1)=1, a(n) = min{5 a(k) + (5^(n-k)-1)/4, k=0..(n-1)} for n>=2.at n=19A259669
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 193", based on the 5-celled von Neumann neighborhood.at n=29A270687
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 931", based on the 5-celled von Neumann neighborhood.at n=22A273790
- Denominator of 2*n*(2*n+1) B_{2*n}, where B_n are the Bernoulli numbers.at n=42A290534