6587
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 26
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 7536
- Proper Divisor Sum (Aliquot Sum)
- 949
- 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
- 5640
- Möbius Function
- 1
- Radical
- 6587
- 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
- 168
- 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
- Fibonacci sequence beginning 4, 15.at n=14A022133
- a(n) = T(2n,n-1), T given by A026648.at n=6A026650
- a(1) = 1, then add, multiply and subtract 2, 3, 4; 5, 6, 7; ... in that order.at n=12A077383
- Number of primes between n^2 and n^3.at n=41A079648
- Start with 1 and repeatedly reverse the digits and add 35 to get the next term.at n=20A118632
- Numbers which are the sum of 3 cubes of distinct odd primes.at n=15A138853
- Numbers which are the sum of three cubes of distinct primes.at n=29A138854
- Number of ways to place zero or more nonadjacent 2,1 3,0 3,1 4,2 4,3 4,4 5,2 6,2 polyhexes in any orientation on a planar nXnXn triangular grid.at n=7A155443
- a(n) = 343*n - 273.at n=19A157369
- a(n) = smallest number that leads to a new cycle under the base-3 Kaprekar map of A164993.at n=9A165009
- Numbers 1 through 10000 sorted lexicographically in ternary representation.at n=44A190128
- Partial sums of the Floor-Sqrt transform of Catalan numbers.at n=15A192633
- Number of n X n X n 0..6 triangular arrays with each element x equal to the number its neighbors equal to 4,3,2,0,1,1,0 for x=0,1,2,3,4,5,6.at n=4A197898
- (A209988)/4.at n=39A209989
- Numbers congruent to 3 in the structure (or curve) of A211000.at n=30A211002
- Number of ordered triples (w,x,y) with all terms in {1,...,n} and w^4>x^4+y^4.at n=28A211653
- Number of values of k for which sigma(k)-k is a permutation of decimal digits of k, for 10^(n-1) < k < 10^n.at n=7A216386
- First differences of number of active (ON, black) cells in n-th stage of growth of two-dimensional cellular automaton defined by "Rule 347", based on the 5-celled von Neumann neighborhood.at n=42A271300
- Integers n such that 10^n + 5^n + 2^n is a prime.at n=10A276741
- Decimal representation of the x-axis, from the left edge to the origin, of the n-th stage of growth of the two-dimensional cellular automaton defined by "Rule 526", based on the 5-celled von Neumann neighborhood.at n=12A282913