16922
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 25386
- Proper Divisor Sum (Aliquot Sum)
- 8464
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8460
- Möbius Function
- 1
- Radical
- 16922
- 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
- 84
- 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
- yes
- Odd
- no
Appears in sequences
- Number of 4-ary search trees on n keys.at n=13A019498
- a(n) = Sum_{k=0..n} (-1)^(n-k)*A000041(k).at n=39A087787
- For a given unrestricted partition pi, let P(pi)=lambda(pi), if mu(pi)=0. If mu(pi)>0 then let P(pi)=nu(pi), where nu(pi) is the number of parts of pi greater than mu(pi), mu(pi) is the number of ones in pi and lambda(pi) is the largest part of pi.at n=38A100818
- Number of 2's in the last section of the set of partitions of n.at n=41A182712
- Number of 2's in all partitions of 2n+1 that do not contain 1 as a part.at n=20A182717
- Number of permutations of 1..n with displacements restricted to {-6,-5,-4,0,1,2,3}.at n=11A189599
- Number of n X n symmetric 0..3 arrays with no element equal to the product mod 4 of any two of its horizontal and vertical neighbors.at n=3A193500
- Numbers k such that R_k - 10 is prime, where R_k = 11...1 is the repunit (A002275) of length k.at n=9A256711
- Number of maximal subsets of {1..n} containing no sums of distinct elements.at n=29A326498
- Table read by antidiagonals: T(w,n) is the number of n-step self avoiding walks on a 3D cubic lattice confined inside a tube of cross section 2w X 2w where the walk starts at the middle of the tube.at n=49A337400
- Indices n where a run of primes ends in A376198.at n=11A376752