16779
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 30
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 5
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 27648
- Proper Divisor Sum (Aliquot Sum)
- 10869
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 8832
- Möbius Function
- 1
- Radical
- 16779
- 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
- 110
- 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) = n*(19*n + 1)/2.at n=42A022277
- a(n) = n*(29*n + 1)/2.at n=34A022287
- Fibonacci sequence beginning 0, 17.at n=16A022351
- Number of partitions satisfying cn(0,5) < cn(1,5) + cn(4,5) + cn(2,5) and cn(0,5) < cn(1,5) + cn(4,5) + cn(3,5).at n=35A039846
- Number of hexagonal regions in regular n-gon with all diagonals drawn.at n=45A067153
- Duplicate of A099920.at n=17A099428
- a(n) = (n+1)*F(n), F(n) = Fibonacci numbers A000045.at n=16A099920
- Number of partitions of 3n+1 into parts >= 3.at n=18A182807
- Coefficients of a generalized Jaco-Lucas polynomial (odd indices) read by rows.at n=37A200073
- Numbers that match polynomials over {0,1} that have a factor containing -3 as a coefficient; see Comments.at n=19A208182
- Indices of record values in A216476.at n=26A216502
- Years >= 1801 in which Christmas falls in Sukkot.at n=41A222419
- Products p*q*r*s of distinct primes for which (p*q*r*s - 1)/2 is prime.at n=33A234498
- Number of length n+5 0..2 arrays with at most one downstep in every n consecutive neighbor pairs.at n=7A255112
- Odd numbers m such that at least one of the factors of Stern polynomial B(m,x) has at least one negative coefficient.at n=16A389915
- Expansion of g^2/(1 + x^2*g^2), where g = 1+x*g^4 is the g.f. of A002293.at n=6A391455