6424
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 16
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 16
- Divisor Sum
- 13320
- Proper Divisor Sum (Aliquot Sum)
- 6896
- Abundant Number
- yes
- Perfect Number
- no
- Deficient Number
- no
- Highly Composite
- no
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 2880
- Möbius Function
- 0
- Radical
- 1606
- Omega Function (Ω)
- 5
- 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
- 23
- 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
- n written in fractional base 8/6.at n=28A024648
- a(n) = Sum_{k=0..2n} (k+1) * A026568(n, k).at n=7A027281
- 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 19.at n=38A031517
- Number of minimal covers of n objects.at n=6A046165
- Let R(i,j) be the rectangle with antidiagonals 1; 2,3; 4,5,6; ...; the n-th Lucas number is in antidiagonal a(n).at n=35A057045
- Numbers n such that x^n + x + 2 is irreducible over GF(3).at n=14A058059
- Numbers k that divide the difference between the sum of the first k partition numbers (A000041) and the sum of the first k unique partition numbers (A000009).at n=5A058228
- Number of orbits of the group of units of Z/(n) acting naturally on the 4-subsets of Z/(n).at n=41A063381
- Sum of the first n safe primes.at n=21A066869
- Decimal concatenations of the quadruples (d1,d2,d3,d4) with elements in {2,4,6} for which there exists a prime p >= 5 such that the differences between the 5 consecutive primes starting with p are (d1,d2,d3,d4).at n=17A078868
- Conjectured lower bound for the number of spheres of radius 1 that can be packed in a sphere of radius n.at n=19A121346
- Minimum k>0 such that Sum_{i=1..n} Fibonacci(i)*k^(i-1) is prime.at n=48A121927
- Numbers k such that k and k^2 use only the digits 1, 2, 4, 6 and 7.at n=24A136993
- a(n) = n*(3*n+14).at n=44A140679
- INVERT transform of (1, 3, 1, 3, 1, ...).at n=9A159612
- Number of n X n binary arrays with rows and columns, considered as binary numbers, in strictly increasing order, and no more than 2 ones in any row or column.at n=6A162101
- Smith numbers of order 2.at n=29A174460
- Number of 3-step king's tours on an n X n board summed over all starting positions.at n=11A186862
- Number of 4-step left-handed knight's tours (moves only out two, left one) on an n X n board summed over all starting positions.at n=16A187174
- G.f.: (1+x)^(2*g)*(1+x^3)^(3*g)/((1-x^2)*(1-x^4))-x^(2*g)*(1+x)^4/((1-x^2)*(1-x^4)) for g=2.at n=59A199628