4405
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 13
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 5292
- Proper Divisor Sum (Aliquot Sum)
- 887
- 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
- 3520
- Möbius Function
- 1
- Radical
- 4405
- 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
- 95
- 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 T1 for Zeolite Code ATO.at n=44A008265
- Numbers k such that the continued fraction for sqrt(k) has period 56.at n=15A020395
- a(n) = Sum_{k >= 1} floor(2*tau^(n-k)).at n=14A020957
- n written in fractional base 8/4.at n=53A024646
- Coordination sequence T6 for Zeolite Code MWW.at n=44A024991
- Triangle T by rows: second differences of Motzkin triangle (A026300), (i >= -1, -1<=j<=i).at n=75A026120
- a(n) = number of (s(0),s(1),...,s(n)) such that every s(i) is a nonnegative integer, s(0) = 1, s(n) = 2, |s(1) - s(0)| = 1, |s(i) - s(i-1)| <= 1 for i >= 2. Also a(n) = T(n,n-1), where T is the array in A026120; a(n) = U(n,n+1), where U is the array in A026148.at n=8A026123
- Coordination sequence T5 for Zeolite Code STT.at n=44A038415
- Numbers whose base-4 representation contains exactly two 0's and four 1's.at n=23A045027
- Becomes prime or 4 after exactly 8 iterations of f(x) = sum of prime factors of x.at n=7A048130
- Numbers k such that the simple continued fraction for (1+1/k)^k contains k.at n=41A071527
- Let u(1)=1, u(n)=2^u(n-1) (mod n), sequence gives values of n such that u(n)=1.at n=42A076825
- Number of compositions (ordered partitions) of n such that some part is repeated consecutively 4 times and no part is repeated consecutively more than 4 times.at n=12A091618
- Expansion of (1-x)/((1-x)^2-3x^3).at n=12A097116
- Indices of primes in sequence defined by A(0) = 19, A(n) = 10*A(n-1) - 11 for n > 0.at n=8A102028
- Number of Fermat pseudoprimes to bases 2, 3 and 5 less than 10^n.at n=10A114248
- The number of closed lambda calculus terms of size n, where size(lambda x.M)=2+size(M), size(M N)=2+size(M)+size(N), and size(V)=1+i for a variable V bound by the i-th enclosing lambda (corresponding to a binary encoding).at n=23A114852
- Retrograde trajectory of 4 under map k -> A094077(k).at n=49A117150
- a(n) = a(n - 1) - 2*a(n - 2) + a(n - 3) - 4*a(n - 4) + 2*a(n - 5).at n=23A122581
- a(n) = least k such that the remainder when 28^k is divided by k is n.at n=32A128368