8556
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 24
- Digital Root
- 6
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 24
- Divisor Sum
- 21504
- Proper Divisor Sum (Aliquot Sum)
- 12948
- 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
- 2640
- Möbius Function
- 0
- Radical
- 4278
- Omega Function (Ω)
- 5
- 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
- yes
Recreational
- Happy Number
- no
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 78
- 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
- a(n) = 2*n*(2*n+1).at n=46A002943
- Constant term in expansion of (1/2) * Product_{k=-n..n} (1 + x^k).at n=9A047653
- Numbers n such that 77*2^n-1 is prime.at n=19A050564
- E.g.f.: -x/(-1+x)*(exp(-x/(-1+x))-1).at n=6A052874
- a(n) = A054145(n)/2.at n=7A054146
- Numbers k such that k^6 == 1 (mod 7^4).at n=21A056092
- a(n) = (n + 2)*(2*n^2 - n + 3)/6.at n=29A056520
- Number of terms from the decimal expansion of Pi (A000796) which include every combination of n digits as consecutive subsequences.at n=2A080597
- a(n) = 10*n^2 + 5*n + 1.at n=29A080860
- Least multiple of n == -1 (mod prime(n)).at n=45A090939
- a(n) = (10^k - n)(10^k + n), where k is the number of digits in n.at n=37A110397
- Numbers k such that k^2 + 11 and k^2 + 13 are primes.at n=35A113537
- Number of permutations of length n which avoid the patterns 132, 3421, 4231.at n=13A116725
- a(n) = prime(n)^2 - prime(n^2). Commutator of (primes, squares) at n.at n=30A123914
- Antidiagonal sums of triangular array T: T(j,1) = 1 for ((j-1) mod 6) < 3, else 0; T(j,k) = T(j-1,k-1) + T(j-1,k) for 2 <= k <= j.at n=27A131025
- Exponent of least power of 2 having exactly n consecutive 4's in its decimal representation.at n=7A131538
- Row sums of triangle A131948.at n=13A131949
- Half the number of ways of placing up to n pawns on a length n chessboard row so that the row balances at its middle.at n=18A133406
- Numbers m such that A137671(m) = 1.at n=11A137674
- Concatenation of first two digits and last two digits of n-th even perfect number.at n=5A138875