4989
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
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 6656
- Proper Divisor Sum (Aliquot Sum)
- 1667
- 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
- 3324
- Möbius Function
- 1
- Radical
- 4989
- 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
- 134
- 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
- Coordination sequence T5 for Zeolite Code MFI.at n=45A008168
- Minimal number of people to give a 50% probability of having at least n coincident birthdays in one year.at n=25A014088
- Numbers k such that the continued fraction for sqrt(k) has period 78.at n=6A020417
- a(n) = a(n-1) + a(n-2) + 1, with a(0) = 1 and a(1) = 11.at n=14A022325
- a(n) = least m such that if r and s in {1/2, 1/5, 1/8, ..., 1/(3n-1)} satisfy r < s, then r < k/m < (k+1)/m < s for some integer k.at n=31A024837
- a(n) = least m such that if r and s in {1/2, 1/4, 1/6, ..., 1/2n} satisfy r < s, then r < k/m < (k+2)/m < s for some integer k.at n=30A024842
- 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 46.at n=27A031544
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 40 ones.at n=16A031808
- a(n) = a(n-1)+ a(round(2*(n-1)/3)) +a(round((n-1)/3)) starting a(1)=1.at n=26A033498
- Denominators of continued fraction convergents to sqrt(303).at n=6A041571
- Numbers whose base-4 representation contains exactly three 1's and three 3's.at n=26A045127
- Numbers whose base-5 representation contains exactly two 2's and three 4's.at n=12A045288
- T(2n,n), array T as in A047040.at n=6A047049
- Discriminants of real quadratic fields with class number 1 and related continued fraction period length of 22.at n=25A051963
- Nearest integer to log(n!)^log(n).at n=13A062422
- Number of nonprimes among the numbers in {1,2,3,...,n!} which are relatively prime to n!.at n=8A067393
- a(1) = 1; a(n) = 3 + n * Sum_{k=1..n-1} a(k).at n=5A082428
- A Binet like formula using the Akiyama-Thurston tile roots for a Minimal Pisot theta0 sequence.at n=31A097600
- Numbers where records occur in A133500.at n=56A133505
- Number of ways of placing kings with no more than 2 mutual attacks on an n X n chessboard symmetric about main diagonal.at n=6A143878