7666
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 11502
- Proper Divisor Sum (Aliquot Sum)
- 3836
- 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
- 3832
- Möbius Function
- 1
- Radical
- 7666
- Omega Function (Ω)
- 2
- Little Omega Function (ω)
- 2
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
- 57
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- yes
- 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
- Numbers k such that the continued fraction for sqrt(k) has even period and if the last term of the periodic part is deleted the central term is 86.at n=17A031584
- a(i) is a square mod a(j), i <> j.at n=20A034903
- Consider the trajectory of n under the iteration of a map which sends x to 3x - sigma(x) if this is >= 0; otherwise the iteration stops. The sequence gives values of n which eventually reach 0.at n=9A037159
- Number of partitions satisfying cn(0,5) <= cn(2,5) + cn(3,5).at n=32A039840
- Numbers having three 6's in base 10.at n=33A043515
- Beastly (or hateful) numbers: numbers containing the string 666 in their decimal expansion.at n=16A051003
- Square spiral of sums of selected preceding terms, starting at 0 followed by 1 (a spiral Fibonacci-like sequence).at n=18A094769
- Numbers n for which there are exactly five k such that n = k + (product of nonzero digits of k).at n=18A096926
- Number of 4 X n 0-1 matrices avoiding simultaneously the right angled numbered polyomino patterns (ranpp) (00;1), (10;0) and (11;0).at n=9A099003
- Index of the first occurrence of A019565(2n-1) in sequence A103790.at n=29A103791
- Near-repdigit semiprimes with 6 as repeated digit.at n=19A105987
- n times n+5 gives the concatenation of two numbers m and m+6.at n=2A116331
- Numbers with composite sum of digits and prime sum of cubes of digits.at n=38A121642
- Numbers k such that k and k^2 use only the digits 0, 5, 6, 7 and 8.at n=6A136963
- Numbers k such that k and k^2 use only the digits 1, 5, 6, 7 and 8.at n=7A137060
- Numbers k such that k and k^2 use only the digits 2, 5, 6, 7 and 8.at n=20A137111
- Numbers k such that k and k^2 use only the digits 3, 5, 6, 7 and 8.at n=4A137132
- Numbers k such that k and k^2 use only the digits 4, 5, 6, 7 and 8.at n=12A137140
- Numbers k such that k and k^2 use only the digits 5, 6, 7 and 8.at n=2A137146
- Numbers k such that k and k^2 use only the digits 5, 6, 7, 8 and 9.at n=4A137147