2827
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 19
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 4
- Divisor Sum
- 3096
- Proper Divisor Sum (Aliquot Sum)
- 269
- 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
- 2560
- Möbius Function
- 1
- Radical
- 2827
- 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
- 110
- 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
- Numbers that are the sum of 6 positive 7th powers.at n=12A003373
- Numbers that are the sum of at most 6 positive 7th powers.at n=48A004868
- Coordination sequence T7 for Zeolite Code MFI.at n=34A008170
- Crystal ball sequence for planar net 3.6.3.6.at n=35A008580
- Convolution of natural numbers >= 2 and natural numbers >= 3.at n=21A023545
- s(1)t(n) + s(2)t(n-1) + ... + s(k)t(n-k+1), where k = [ n/2 ], s = (odd natural numbers), t = A001950 (upper Wythoff sequence).at n=17A025114
- Lucky numbers with size of gaps equal to 8 (lower terms).at n=32A031890
- Numbers n such that string 8,1 occurs in the base 9 representation of n but not of n-1.at n=37A044324
- Numbers n such that string 2,7 occurs in the base 10 representation of n but not of n-1.at n=31A044359
- Numbers n such that string 8,1 occurs in the base 9 representation of n but not of n+1.at n=37A044705
- Numbers n such that string 2,7 occurs in the base 10 representation of n but not of n+1.at n=31A044740
- Number of nonempty subsets of {1,2,...,n} in which exactly 5/6 of the elements are <= n/2.at n=20A047170
- Number of nonempty subsets of {1,2,...,n} in which exactly 5/6 of the elements are <= (n-1)/2.at n=20A047181
- Becomes prime after exactly 6 iterations of f(x) = sum of prime factors of x.at n=23A047825
- 3*n^2-2*n+6.at n=31A047915
- a(n)=number of numbers h^2+k^2 that are <=2n^2; equivalently, a(n)=T(n,n), array T as in A048149.at n=42A048150
- Starting positions of strings of 2 4's in the decimal expansion of Pi.at n=24A050230
- Numbers k such that 285*2^k-1 is prime.at n=23A050901
- Expansion of g.f.: (1-2*x)/(1-3*x+2*x^3).at n=9A052948
- Least m such that card(invphi(phi(m)))=n.at n=24A066420