6572
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 12
- Divisor Sum
- 12096
- Proper Divisor Sum (Aliquot Sum)
- 5524
- 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
- 3120
- Möbius Function
- 0
- Radical
- 3286
- Omega Function (Ω)
- 4
- 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
- 75
- 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 hexagonal polyominoes (or hexagonal polyforms, or planar polyhexes) with n cells.at n=8A000228
- Sum of 12 nonzero 8th powers.at n=13A003390
- Number of degenerate fanout-free Boolean functions of n variables using And, Or, Not and Majority gates.at n=4A005742
- Erroneous version of A000228.at n=8A014558
- Numbers k such that sigma(k) = sigma(k+6).at n=24A015866
- Nine iterations of Reverse and Add are needed to reach a palindrome.at n=41A015990
- (d(n)-r(n))/5, where d = A026046 and r is the periodic sequence with fundamental period (1,0,4,0,0).at n=42A026048
- Numbers n such that there are equal numbers of 0's and 1's in first n digits of binary representation of Pi.at n=32A039624
- Sum of absolute values of coefficients of expansion of (1-x)(1-x^2)(1-x^3)...(1-x^n).at n=33A061553
- Zero, together with positive numbers k such that prime(k) + k is a square.at n=28A064371
- Potential Sierpiński numbers: integers for which the smallest m > 2^10 in A040076 such that n*2^m+1 is prime (A050921).at n=22A064721
- Numbers which need nine 'Reverse and Add' steps to reach a palindrome.at n=40A065214
- Numbers which are the sum of three positive cubes and divisible by 31.at n=32A104054
- Numbers n such that n+prime(n) is the square of a prime.at n=6A104911
- Numbers n such that prime(n) + n is a perfect power.at n=33A107605
- Numbers n such that prime(n) + n is a prime power (A246547).at n=12A109314
- Numbers k such that k*(k+2) gives the concatenation of two numbers m and m+8.at n=5A116344
- Number of polyominoes consisting of 9 regular unit n-gons.at n=3A120103
- Triangle T(n,k), 0 <= k <= n, read by rows defined by: T(0,0)=1, T(n,k)=0 if k < 0 or if k > n, T(n,0) = 4*T(n-1,0) + T(n-1,1), T(n,k) = T(n-1,k-1) + 5*T(n-1,k) + T(n-1,k+1) for k >= 1.at n=41A126331
- a(n) is equal to the number of positive integers m less than or equal to 10^n such that m is not divisible by the prime 3 and is not divisible by at least one of the primes 2, 5 and 7.at n=2A128952