8949
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
- 8
- Divisor Sum
- 12640
- Proper Divisor Sum (Aliquot Sum)
- 3691
- 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
- 5616
- Möbius Function
- -1
- Radical
- 8949
- 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
- 91
- 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
- Continued cotangent for e.at n=3A002668
- Number of 3's in n-th term of A007651.at n=38A022468
- Numerators of continued fraction convergents to sqrt(465).at n=8A041886
- a(n) = a(n-1) + a(m) for n >= 4, where m = 2*n - 2 - 2^(p+1) and p is the unique integer such that 2^p < n - 1 <= 2^(p+1), starting with a(1) = a(2) = 1 and a(3) = 3.at n=30A050035
- Number of nonprimes <= prime(n)^2.at n=25A053683
- Numbers n such that sum of primes dividing n (with repetition) is equal to the largest prime factor of n+1.at n=14A071863
- a(1) = 9; a(n) is smallest number > a(n-1) such that the juxtaposition a(1)a(2)...a(n) is a prime.at n=46A074345
- Number of consecutive prime runs of 9 primes congruent to 3 mod 4 below 10^n.at n=8A092661
- Union of A071863 and A071861.at n=31A193458
- Unhappy numbers which enter the cycle (4, 16, 37, 58, 89, 145, 42, 20) at 20.at n=43A193572
- Numbers that match polynomials over {0,1} that have a factor containing 3 as a coefficient; see Comments.at n=16A208181
- Numbers k such that A112141(k) - 1 is prime.at n=19A224082
- Least odd number d such that the Collatz (3x+1) iteration of d has the following property: if the length of the iteration is b and the maximum value occurs at c, the ratio c/b is 1/n.at n=45A224994
- G.f.: Sum_{n>=0} x^n / Product_{k=n..2*n-1} (1 - k*x).at n=7A249636
- Partial sums of the number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 486", based on the 5-celled von Neumann neighborhood.at n=28A272508
- Andrews's shadow difference function D_3(q).at n=37A275633
- Ulam numbers n such that 3*n is also an Ulam number.at n=38A285885
- a(n) = Sum_{k=1..n} k * tau_3(k), where tau_3 is A007425.at n=38A318750
- Number of regions after generation n of Conant's dissection of a square when dissected with diagonal lines.at n=16A334630
- Numbers that are the sum of ten fourth powers in exactly eight ways.at n=37A345860