7766
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 26
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 5
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 12744
- Proper Divisor Sum (Aliquot Sum)
- 4978
- 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
- 3520
- Möbius Function
- -1
- Radical
- 7766
- Omega Function (Ω)
- 3
- 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
- no
- Narcissistic Number
- no
- Collatz Steps
- 52
- 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
- Landau's approximation to population of x^2 + y^2 <= 2^n.at n=15A000690
- Character of extremal vertex operator algebra of rank 33/2.at n=3A028538
- Least term in period of continued fraction for sqrt(n) is 8.at n=24A031432
- Numbers k such that 255*2^k+1 is prime.at n=32A032504
- Squarefree n such that the elliptic curve n*y^2 = x^3 - x arising in the "congruent number" problem has rank 3.at n=10A062693
- List of codewords in binary lexicode with Hamming distance 5 written as decimal numbers.at n=29A075931
- Fourth diagonal (m=3) of triangle A084938; a(n) = A084938(n+3,n) = (n^3 + 9*n^2 + 26*n)/6.at n=33A092286
- Smallest number not occurring earlier fitting the repeating pattern "99887766554433221100".at n=36A098782
- Partial sums of A005587. Fourth column of triangle A115127.at n=10A115129
- a(n) = Sum_{k=1..phi(n)} k*t(k), where t(k) is the k-th positive integer which is coprime to n and phi(n) is the number of positive integers which are <= n and are coprime to n.at n=38A135324
- a(n) = 16n^2 + n.at n=21A157474
- One-eighth of triangular numbers (integers only).at n=44A157716
- a(n) = 64*n^2 + 2*n.at n=11A158070
- a(n) = 484*n^2 + 22.at n=4A158629
- a(n) = 4*n^2 + floor(n/2).at n=44A173511
- a(n) = a(n-1) + A073053(a(n-1)).at n=34A173578
- Numbers m such that the sum of square of factorial of decimal digits is square.at n=41A173689
- Number of (w,x,y,z) with all terms in {1,...,n} and w+x<=y+z.at n=11A212560
- Numbers which have only digits 6 and 7 in base 10.at n=26A256292
- Expansion of Product_{k>=1} 1/(1 - (4*k-2)*x^(4*k-2)).at n=22A265829