6699
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 30
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 11520
- Proper Divisor Sum (Aliquot Sum)
- 4821
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 3360
- Möbius Function
- 1
- Radical
- 6699
- 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
- 137
- 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
- Strobogrammatic numbers: the same upside down.at n=26A000787
- Orders of cyclotomic polynomials containing a coefficient the absolute value of which is >= 5.at n=27A013593
- Numbers k such that sigma(k) = sigma(k+7).at n=14A015867
- Character of extremal vertex operator algebra of rank 21/2.at n=4A028530
- Squarefree odd numbers with exactly 4 distinct prime factors.at n=38A046390
- Numbers that are unchanged when turned upside down, when written in a font in which 7 looks like upside-down 2.at n=44A051791
- Numbers m such that there are precisely 3 groups of order m.at n=34A055561
- Composites for which the row of the prime-composite array (A063173) includes the leftmost element of both a zero-only antidiagonal and a zero-only diagonal(A067681).at n=40A063176
- Dimension of the space of weight n cuspidal newforms for Gamma_1( 67 ).at n=36A063340
- 2-apexes of omega: numbers k such that omega(k-2) < omega(k-1) < omega(k) > omega(k+1) > omega(k+2), where omega(m) = the number of distinct prime factors of m.at n=36A076762
- Stable Poincaré series [or Poincare series] for Lie algebra of types B or C.at n=19A098789
- Expansion of x^4 / ((x+1)*(2*x^3-2*x^2-2*x+1)*(x-1)^2).at n=13A110158
- Numbers that look the same when rotated by 180 degrees, using only digits 0, 6 and 9.at n=6A111065
- Numbers that look the same when printed upside down.at n=12A111156
- 4-almost primes with semiprime digits (digits 4, 6, 9 only).at n=14A111496
- a(n) = n*(8*n-1).at n=29A139274
- Number of binary strings of length n with no substrings equal to 0001 0101 or 1000.at n=12A164471
- a(n) = A168174(n)-10^12.at n=8A168248
- Numbers that are the same upside down (using only digits 0, 1, 6 and 9).at n=17A169731
- Losing positions in Nim (misere) with up to 9 stones on each heap.at n=64A190588