6978
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 30
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 13968
- Proper Divisor Sum (Aliquot Sum)
- 6990
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- yes
Derived Values
- Euler's Totient
- 2324
- Möbius Function
- -1
- Radical
- 6978
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 88
- 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
- Number of words of length n in a certain language.at n=39A005819
- a(n) = floor( n*(n-1)*(n-2)/19 ).at n=52A011901
- a(n+1) = Sum_{k=0..floor(3*n/4)} a(k) * a(n-k).at n=13A030035
- 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 82.at n=19A031580
- Number of 6-ary rooted trees with n nodes and height exactly 4.at n=17A036642
- Number of orbits of length n under the automorphism of the 3-torus whose periodic points are counted by A001945.at n=44A060169
- Least k such that k*11^n +/- 1 are twin primes.at n=22A064220
- a(n) = 4^n mod n^4.at n=10A066608
- Left truncatable 3-almost primes, in which repeatedly deleting the leftmost digit gives a 3-almost prime at every step until a single-digit 3-almost prime remains.at n=44A085248
- a(n) = round(n^3/12) - floor(n/4)*floor((n+2)/4).at n=44A090676
- Expansion of A(x)^2, where A(x) = o.g.f. of n^n (A000312).at n=5A100262
- Rectangular table, read by antidiagonals, such that the g.f. of row n, R_n(y), satisfies: R_n(y) = Sum_{k>=0} y^k * R_k(y)^(n*k) for n>=0, with R_0(y) = 1/(1-y).at n=53A124530
- Row 1 of rectangular table A124530.at n=8A124531
- Rectangular table, read by antidiagonals, such that the g.f. of row n, R_n(y), satisfies: R_n(y) = [ Sum_{k>=0} y^k * R_k(y)^n ]^n for n>=0, with R_0(y) = 1.at n=53A124540
- Number of nX2 0..4 arrays with each element x equal to the number its horizontal and vertical neighbors equal to 3,0,4,1,2 for x=0,1,2,3,4.at n=12A196140
- (k(n)!-j(n)!)/n, where (k!,j!) is the least pair of distinct factorials for which n divides k!-j!.at n=51A204937
- 5*n^2 + 4*n - 15.at n=36A239794
- Number of partitions p of n such that exactly one number is in both p and its conjugate.at n=38A240675
- Number of (n+2) X (1+2) 0..3 arrays with no row, column, diagonal or antidiagonal in any 3 X 3 subblock summing to 0 2 4 5 7 or 9.at n=6A251645
- Number of (n+2)X(7+2) 0..3 arrays with no row, column, diagonal or antidiagonal in any 3X3 subblock summing to 0 2 4 5 7 or 9.at n=0A251651