7690
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 13860
- Proper Divisor Sum (Aliquot Sum)
- 6170
- 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
- 3072
- Möbius Function
- -1
- Radical
- 7690
- 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
- Coordination sequence for body-centered tetragonal lattice.at n=31A008527
- Minimal number of people to give a 50% probability of having at least n coincident birthdays in one year.at n=35A014088
- Least k>1 such that reverse of first n terms of A006928 repeats beginning at k-th term.at n=49A025509
- Least k>1 such that reverse of first n terms of A022303 repeats beginning at k-th term.at n=43A025520
- Shifts left 2 places under "DHK" (bracelet, identity, unlabeled) transform.at n=17A032258
- Boris Stechkin's function.at n=26A055004
- S[A002808(n)] where S[] is Boris Stechkin's function (A055004) and A002808(n) are the composites.at n=17A063483
- Engel expansion of sin(2).at n=10A067920
- a(0) = 1, a(n) = Sum_{k=1..n} A001263(n,k)*a(k-1) where A001263(n,k) are Narayana numbers.at n=7A102812
- a(n) = (2*n-1)^2 + (2*n+1)^2.at n=31A108100
- Number of partitions of n into 5-smooth parts.at n=34A112581
- Number of partitions of n into at least two parts such that the product of largest and smallest part exceeds n.at n=52A116902
- Engel expansion of L(3, chi3), where L(s, chi3) is the Dirichlet L-function for the non-principal character modulo 3.at n=7A129409
- Eigentriangle of A001263: T(n,k) = A001263(n+1,k+1)*A102812(k).at n=35A143778
- Number of nondecreasing integer sequences of length 10 with sum zero and sum of absolute values 2n.at n=13A158144
- Integers of the form: 0/3 + 1/3 + 2/3 + 3/3 + 5/3 + 7/3 + 11/3 + 13/3 + 17/3 + ....at n=36A182155
- E.g.f. satisfies: A(x) = 1 + Sum_{n>=1} 2*cosh(n*x) * (x*A(x))^(n^2).at n=5A199576
- Number of 2 X 2 matrices with all terms in {0,1,...,n} and (sum of terms) = n + 4.at n=30A210376
- a(n) = a(n-1) + a(n-2) + a(n-3), with a(0) = 1, a(1) = a(2) = 8.at n=13A214830
- Numbers n such that the digits of sigma(n) are a permutation of those of sigma*(n), where sigma*(n) is the sum of anti-divisors of n (A066417).at n=38A230541