6128
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 17
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 10
- Divisor Sum
- 11904
- Proper Divisor Sum (Aliquot Sum)
- 5776
- 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
- 3056
- Möbius Function
- 0
- Radical
- 766
- Omega Function (Ω)
- 5
- 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
- 49
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- no
- Composite Number
- yes
- Semiprime
- no
- Squarefree Number
- no
- 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
- Number of permutations of [n] with no 3-term arithmetic progression.at n=12A003407
- The larger of a betrothed pair.at n=5A003503
- Betrothed (or quasi-amicable) numbers.at n=11A005276
- Number of equivalence classes of n X n binary matrices when one can permute rows, permute columns and complement columns.at n=6A006383
- Coordination sequence for CaF2(2), Ca position.at n=35A009926
- T(2n,n-1), T given by A026714.at n=5A026716
- Concatenate n-th prime and n-th composite.at n=17A038530
- Larger members of g-reduced amicable pairs a < b such that sigma(a) = sigma(b) = a + b + gcd(a,b).at n=23A054572
- Layer counting sequence for hyperbolic tessellation by cuspidal triangles of angles (Pi/3, Pi/5, Pi/7).at n=14A054887
- Number of n X 6 binary matrices under row and column permutations and column complementations.at n=6A056205
- a(n) = Sum_{k = 1..n, gcd(k,n)=1} k*(n-k).at n=47A057789
- Numbers k such that k*2^m+1 are composites for all exponents m in the range 0<=m<=k.at n=18A061153
- Potential Sierpiński numbers: integers for which the smallest m > 2^10 in A040076 such that n*2^m+1 is prime (A050921).at n=20A064721
- Let u(1)=u(2)=1, u(3)=2n, u(k) = abs(u(k-1)-u(k-2)-u(k-3)) and M(k) = Max_{i<=i<=k} u(i), then for any k >= A078109(n), M(k) = floor(sqrt(k + a(n))).at n=13A078108
- Least non-balanced x (i.e., not in A020492) such that sigma(2n-1,x)/phi(x) is an integer.at n=8A078539
- Least non-balanced x (i.e., not in A020492) such that sigma(p(n),x)/phi(x) is an integer, where p(n) = n-th prime.at n=7A078540
- a(n) = floor(Product_{i=1..n} log(prime(i+1))/log(i+1)).at n=23A089223
- a(n) = 16*(8*prime(n) + 7).at n=14A098823
- Numbers n such that (10^n-1)^2-2 is prime.at n=5A100903
- Number of orbits of the 5-step recursion mod n.at n=37A106287