2683
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
- 4
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 2684
- Proper Divisor Sum (Aliquot Sum)
- 1
- 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
- 2682
- Möbius Function
- -1
- Radical
- 2683
- Omega Function (Ω)
- 1
- Little Omega Function (ω)
- 1
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
- 71
- Smith Number
- no
- Vampire Number
- no
Primality
- Prime
- yes
- Composite Number
- no
- Semiprime
- no
- Squarefree Number
- yes
- Prime Power
- yes
- Prime Factorization
- no
- Twin Prime
- no
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 389
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Largest prime p==3 (mod 8) such that Q(sqrt(-p)) has class number 2n+1.at n=2A002149
- a(n) = a(n-1) + 3*a(n-2) for n > 1, a(0) = a(1) = 1.at n=10A006130
- Prime self (or Colombian) numbers: primes not expressible as the sum of an integer and its digit sum.at n=41A006378
- Primes of form 2n^2 - 2n + 19.at n=30A007639
- Expansion of (1+x^9)/((1-x)*(1-x^2)*(1-x^3)*(1-x^4)).at n=57A008770
- Numbers k such that the continued fraction for sqrt(k) has period 58.at n=5A020397
- Initial members of prime triples (p, p+4, p+6).at n=29A022005
- Primes that remain prime through 2 iterations of function f(x) = 9x + 4.at n=37A023266
- a(n) = position of 3*n^3 in A003072.at n=19A024970
- a(n) = [ 2nd elementary symmetric function of {log(k)} ], k = 2,3,...,n.at n=27A025202
- (d(n)-r(n))/5, where d = A026046 and r is the periodic sequence with fundamental period (1,0,4,0,0).at n=30A026048
- Sequence satisfies T^2(a)=a, where T is defined below.at n=42A027594
- a(n) = T(n, 2*n-7), T given by A027926.at n=9A027930
- a(n) = T(2n+1, n+3), T given by A027948.at n=4A027955
- a(n) = greatest number in row n of array T given by A027948.at n=13A027957
- Greatest number in row n of array T given by A027926.at n=13A027988
- a(n) = prime(10*n - 1).at n=38A031376
- 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 51.at n=8A031549
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 32 ones.at n=7A031800
- Functions of n points with no symmetries.at n=10A032176