16870
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 34848
- Proper Divisor Sum (Aliquot Sum)
- 17978
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Weird Number
- yes
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 5760
- Möbius Function
- 1
- Radical
- 16870
- 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
- 58
- 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=26A006037
- Numbers k such that 135*2^k-1 is prime.at n=26A050593
- Unitary weird numbers: unitary abundant (A034683) but not unitary pseudoperfect (A293188).at n=23A064114
- Number of n X n binary arrays symmetric under horizontal reflection with all ones connected only in a 1100-0111-1100 pattern in any orientation.at n=10A146675
- a(n) = Sum_{k=1..n} (k+2)!/k! = Sum_{k=1..n} (k+2)*(k+1).at n=35A180118
- T(n,k)=number of nXk binary matrices with floor((n*k)/2) 1's and rows and columns in lexicographically nondecreasing order.at n=58A180979
- T(n,k)=number of nXk binary matrices with floor((n*k)/2) 1's and rows and columns in lexicographically nondecreasing order.at n=62A180979
- Number of nX4 0..1 arrays with rows and columns lexicographically nondecreasing and the instance counts of every value within one of each other.at n=7A201380
- T(n,k)=Number of nXk 0..1 arrays with rows and columns lexicographically nondecreasing and the instance counts of every value within one of each other.at n=58A201384
- T(n,k)=Number of nXk 0..1 arrays with rows and columns lexicographically nondecreasing and the instance counts of every value within one of each other.at n=62A201384
- Sum of the smallest parts of the partitions of 4n into 4 parts.at n=18A238702
- Value of the n-th Roman number interpreted as Latin alphabetic number.at n=24A285511
- Number of independent vertex sets and vertex covers in the n X n queen graph.at n=7A287227
- Bi-unitary weird numbers: bi-unitary abundant numbers (A292982) that are not bi-unitary pseudoperfect (A292985).at n=28A292986
- Infinitary weird numbers: infinitary abundant numbers (A129656) that are not infinitary pseudoperfect numbers (A306983).at n=28A306984
- Number of non-isomorphic self-dual set multipartitions (multisets of sets) of weight n.at n=18A321403
- Nonexponential weird numbers: nonexponential abundant numbers (A348604) that are not equal to the sum of any subset of their nonexponential divisors.at n=21A348631
- (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=22A349285
- Weird untouchable numbers.at n=7A357326
- Expansion of e.g.f. exp(x^3) / (1 - x * exp(x^3/6)).at n=7A375634