6606
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 18
- Digital Root
- 9
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 14352
- Proper Divisor Sum (Aliquot Sum)
- 7746
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2196
- Möbius Function
- 0
- Radical
- 2202
- Omega Function (Ω)
- 4
- Little Omega Function (ω)
- 3
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
- yes
- Narcissistic Number
- no
- Collatz Steps
- 75
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- Coordination sequence for MgNi2, Position Ni1.at n=20A009933
- Otto Haxel's guess for magic numbers of nuclear shells.at n=27A033547
- Number of partitions of n into parts not of the form 25k, 25k+4 or 25k-4. Also number of partitions with at most 3 parts of size 1 and differences between parts at distance 11 are greater than 1.at n=33A036003
- Number of partitions satisfying (cn(0,5) = cn(2,5) = cn(3,5) and cn(0,5) <= cn(1,5) and cn(0,5) <= cn(4,5)).at n=54A036821
- Numbers having three 0's in base 9.at n=20A043455
- Numbers having three 6's in base 10.at n=12A043515
- A hierarchical sequence (S(W3{2,2}cc) - see A059126).at n=6A059138
- Numbers which are the sum of their proper divisors containing the digit 0.at n=41A059461
- Binomial transform of (1,0,1,0,1,0,1,1,1,1,1,...).at n=13A084637
- When A058033 first reaches n.at n=16A084972
- Let A denote the sequence; then A is equal to the union of the self-convolutions A^2 and A^4, with terms in ascending order by size, where a(0)=1.at n=23A090847
- Numbers k such that (10's complement factorial of k) - 1 is prime.at n=16A109617
- Semi-diagonal (two rows below central terms) of pendular triangle A118345 and equal to the self-convolution cube of the central terms (A118346).at n=5A118348
- Convolution triangle, read by rows, where diagonals are successive self-convolutions of A118346.at n=41A118349
- a(n) = 9 + floor( Sum_{j=1..n-1} a(j)/3 ).at n=23A120154
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, 1), (-1, 1, 0), (0, 0, 1), (0, 1, -1), (1, 0, 1)}.at n=7A150407
- Number of walks within N^3 (the first octant of Z^3) starting at (0,0,0) and consisting of n steps taken from {(-1, -1, -1), (-1, -1, 0), (0, 1, -1), (1, 0, 0), (1, 1, 1)}.at n=7A150454
- Numbers k such that k^81*(k^81+1)+1 is prime.at n=28A153442
- If 0 <= n <= 3 then a(n) = n(n+1)(n+2)/3, if n >= 4 then a(n) = n(n^2+5)/3.at n=27A162626
- Numbers m such that (6*m)^5 is a sum of a twin prime pair.at n=33A173560