6591
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 21
- Digital Root
- 3
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 8
- Divisor Sum
- 9520
- Proper Divisor Sum (Aliquot Sum)
- 2929
- 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
- 4056
- Möbius Function
- 0
- Radical
- 39
- Omega Function (Ω)
- 4
- 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
- 243
- 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
- no
- Odd
- yes
Appears in sequences
- Numbers k that divide s(k), where s(1)=1, s(j)=3*s(j-1)+j.at n=4A014850
- Numbers k that divide s(k), where s(1)=1, s(j)=9*s(j-1)+j.at n=31A014857
- Integers k such that k divides 22^k - 1.at n=44A014959
- Numbers k that divide the (right) concatenation of all numbers <= k written in base 13 (most significant digit on left).at n=33A029458
- 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 54.at n=20A031552
- Numbers k such that s(k) + s(k+1) + s(k+2) = t(k) + t(k+1) + t(k+2) where s(k) = sigma(k) - k, t(k) = |s(k) - k|.at n=6A033910
- Numbers k that divide 7^k + 2^k.at n=26A045580
- Numbers k that divide 7^k + 5^k.at n=22A045596
- Composite numbers with four prime factors (not necessarily distinct) whose concatenation yields a palindrome.at n=7A046453
- Number of primitive (period n) periodic palindromic structures using a maximum of three different symbols.at n=18A056514
- Numbers n such that n | 9^n + 8^n + 7^n + 6^n + 5^n + 4^n.at n=23A057260
- Numbers k such that k | 8^k + 7^k + 6^k + 5^k + 4^k + 3^k.at n=41A057261
- Numbers k such that k | 12^k + 11^k + 10^k + 9^k + 8^k + 7^k + 6^k + 5^k + 4^k + 3^k + 2^k + 1^k.at n=48A057291
- Nearest integer to (n+1)^3/9.at n=38A060999
- a(n) = floor(n^3/9).at n=39A061263
- Number of divisors of n equals the average of distinct prime factors of n.at n=28A067547
- Numbers n such that sopf(sigma(n)) = sigma(sopf(n)), where sopf(x) = sum of the distinct prime factors of x.at n=19A076532
- Hypotenuses for which there exist exactly 3 distinct integer triangles.at n=35A084647
- Numbers n such that the Zsigmondy number Zs(n,3,1) differs from the n-th cyclotomic polynomial evaluated at 3.at n=48A093107
- Smallest number which requires n iterations to reach a prime when iterating x + sum of squares of digits of x.at n=28A094658