7827
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
- 4
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 10440
- Proper Divisor Sum (Aliquot Sum)
- 2613
- 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
- 5216
- Möbius Function
- 1
- Radical
- 7827
- 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
- 145
- 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
- no
- Odd
- yes
Appears in sequences
- Number of free nonplanar polyenoids with n nodes.at n=6A000953
- From a nim-like game.at n=33A003413
- Cycle class sequence c(n) (the number of true cycles of length n in which a certain node is included) for zeolite BEA = Beta Na7[Al7Si57O128] starting with a T6 atom.at n=12A019072
- 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 87.at n=25A031585
- Lucky numbers with size of gaps equal to 14 (upper terms).at n=39A031897
- "BFK" (reversible, size, unlabeled) transform of 1,3,5,7...at n=12A032046
- Multiplicity of highest weight (or singular) vectors associated with character chi_29 of Monster module.at n=37A034417
- Denominators of continued fraction convergents to sqrt(891).at n=8A042723
- a(n)^2 is a square whose digits occur with an equal minimum frequency of 2.at n=31A052049
- Number of (simple, undirected, unlabeled, connected) graphs with n vertices which contain no induced subgraph isomorphic to a C5 (the cycle on 5 vertices).at n=7A078566
- a(n) = 4*n^2 + 10*n + 1.at n=43A082112
- Binomial transform of A088689.at n=13A088688
- Semiprimes which are the sum of two pentagonal numbers (A000326) in exactly two different ways.at n=43A120536
- Average of Eulerian numbers (A008292) and Pascal's triangle (A007318): t(n,m) = (A008292(n,m) + A007318(n,m))/2.at n=31A141689
- Average of Eulerian numbers (A008292) and Pascal's triangle (A007318): t(n,m) = (A008292(n,m) + A007318(n,m))/2.at n=32A141689
- 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, 0), (-1, 0, -1), (0, -1, 1), (0, 1, 0), (1, 0, 0)}.at n=8A149927
- Number of composite numbers between exponents of successive Mersenne primes.at n=22A157894
- a(n) = (1/2)*(n^3 - 6*n^2 + 13*n - 6).at n=26A158498
- Number of tilings of a 3 X n rectangle using dominoes and right trominoes.at n=8A165716
- Triangle, read by rows, T(n, k) = 1 - floor(n*(n-1)/4) + floor(binomial(n-1,k-1) * binomial(n, k-1)/(2*k)).at n=57A176125