7689
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
- 11232
- Proper Divisor Sum (Aliquot Sum)
- 3543
- 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
- 4640
- Möbius Function
- -1
- Radical
- 7689
- 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
- 57
- 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
- no
- Odd
- yes
Appears in sequences
- Least m such that if r and s in {1/4, 1/8, 1/12, ..., 1/4n} satisfy r < s, then r < k/m < (k+1)/m < s for some integer k.at n=33A024839
- Least k>1 such that reverse of first n terms of A006928 repeats beginning at k-th term.at n=50A025509
- Least k>1 such that reverse of first n terms of A022303 repeats beginning at k-th term.at n=44A025520
- Size of lexicographic code of length n, Hamming distance 6 and weight 6.at n=42A031504
- Number of identity bracelets of n beads of 3 colors.at n=10A032240
- Denominator of L(n) = (Sum_{k=1..n} k^n)/(Sum_{k=1..n-1} k^n).at n=5A043300
- McKay-Thompson series of class 35B for Monster.at n=38A058641
- Integers n > 7059 such that the 'Reverse and Add!' trajectory of n joins the trajectory of 7059.at n=6A063058
- Numbers n such that phi(3n+1) = sigma(n).at n=44A067233
- Numbers k such that sigma(k) = phi(k*bigomega(k)+1).at n=37A067876
- Numbers k such that sigma(k) = phi(k*omega(k)+1).at n=37A067879
- Third row of Pascal-(1,3,1) array A081578.at n=31A081585
- Symmetric square table of coefficients, read by antidiagonals, where T(n,k) is the coefficient of x^n*y^k in f(x,y) that satisfies: f(x,y) = g(x,y) + xy*f(x,y)^4 and where g(x,y) satisfies: 1 + (x+y-1)*g(x,y) + xy*g(x,y)^2 = 0.at n=57A089447
- Odd interprimes divisible by 11.at n=37A126230
- 3 times 13-gonal (or tridecagonal) numbers: a(n) = 3*n*(11*n - 9)/2.at n=22A153875
- a(n) = 961*n + 1.at n=7A158414
- Numbers k such that 8*k! + 1 is prime.at n=19A178488
- Number of 2 X 2 matrices having all elements in {0,1,...,n} and determinant in the closed interval [-n,n].at n=12A211031
- McKay-Thompson series of class 35B for the Monster group with a(0) = 1.at n=38A212253
- Shifts 6 places left under Euler transform with a(0)=0 and a(n)=1 for n<6.at n=28A218023