16730
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 34560
- Proper Divisor Sum (Aliquot Sum)
- 17830
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- yes
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5712
- Möbius Function
- 1
- Radical
- 16730
- Omega Function (Ω)
- 4
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 40
- 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
- Weird numbers: abundant (A005101) but not pseudoperfect (A005835).at n=25A006037
- Expansion of e.g.f.: exp(tan(x).exp(x)).at n=7A009248
- Coordination sequence for Ni2In, Position Ni1 and In.at n=39A009941
- Number of ordered rooted trees with n non-root nodes and all outdegrees <= seven.at n=10A036769
- a(0)=0, a(1)=2 then a(n) = a(n-2) + 2*sqrt(8*a(n-1)^2 + 8*a(n-1) + 1).at n=6A053141
- a(n) = Sum_{k divides n} (n/k)^k.at n=23A055225
- Unitary weird numbers: unitary abundant (A034683) but not unitary pseudoperfect (A293188).at n=22A064114
- a(n) = (2*Pell(n+1) - (1+(-1)^n))/4.at n=12A105635
- The number of permutations p of {1,...,n} such that |p(i)-p(i+1)| is in {3,4} for all i from 1 to n-1.at n=28A174706
- Table a(k,i), read by antidiagonals, in which the n-th row comprises A214206(n) in position 0 followed by a second order recursive series G in which each product G(i)*G(i+1) lies in the same row of A001477 (interpreted as a square array - see below).at n=38A182439
- Years >= 1801 in which Christmas falls in Sukkot.at n=36A222419
- T(n,k)=Number of nXk 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest or zero plus the sum of the elements antidiagonally to its northeast, modulo 4.at n=46A240760
- Number of 2Xn 0..3 arrays with no element equal to one plus the sum of elements to its left or zero plus the sum of the elements above it or zero plus the sum of the elements diagonally to its northwest or zero plus the sum of the elements antidiagonally to its northeast, modulo 4.at n=8A240761
- Numbers n such that n^2 + (n+1)^2 is equal to the sum of the hexagonal numbers H(m) and H(m+1) for some m.at n=3A251867
- Bi-unitary weird numbers: bi-unitary abundant numbers (A292982) that are not bi-unitary pseudoperfect (A292985).at n=27A292986
- Infinitary weird numbers: infinitary abundant numbers (A129656) that are not infinitary pseudoperfect numbers (A306983).at n=27A306984
- Numbers k such that N = k^6 is a twin rank (cf. A002822: 6N +- 1 are twin primes).at n=10A326236
- Nonexponential weird numbers: nonexponential abundant numbers (A348604) that are not equal to the sum of any subset of their nonexponential divisors.at n=20A348631
- (1+e)-weird numbers: (1+e)-abundant numbers k such that no subset of the aliquot (1+e)-divisors of k sums to k.at n=21A349285
- S-weird numbers: S-abundant numbers (A181487) k such that no subset of the aliquot divisors of k that are in the set S sums to k, where S is the set defined in A118372.at n=40A364862