8681
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 5
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 8682
- 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
- 8680
- Möbius Function
- -1
- Radical
- 8681
- 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
- 78
- 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
- 1081
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Numbers k such that the continued fraction for sqrt(k) has period 83.at n=2A020422
- Primes that do not contain any other prime as a proper substring.at n=48A033274
- Primes with multiplicative persistence value 5.at n=21A046505
- Primes p whose reciprocal has period (p-1)/10.at n=13A056215
- Primes p such that x^31 = 2 has no solution mod p.at n=31A059225
- Primes with 15 as smallest positive primitive root.at n=3A061328
- Primes for which the smallest positive primitive root is odd and nonprime.at n=6A070269
- Initial terms of groups in A075639.at n=46A075641
- First column of square array A082011.at n=46A082013
- Expansion of e.g.f.: 1/(1-sinh(x)-x-x^2).at n=5A088189
- Primes of the form 6*p - 1 such that p and 6*p - 5 are primes.at n=35A090609
- Primes which are also prime if their base 31 representation is interpreted as a base 10 number.at n=42A090715
- Duplicate of A056215.at n=13A098677
- Number of nonisomorphic groups with orders indexed by least prime signatures.at n=32A098887
- Primes from merging of 4 successive digits in decimal expansion of cos(1).at n=1A104960
- a(n) = Sum_{k=1..n} J_4(k)/240.at n=20A115003
- Primes of the form 41*x^2+38*x*y+41*y^2.at n=34A140013
- Primes of the form 8x^2+8xy+233y^2.at n=32A140033
- Primes of the form 210n+71.at n=21A140856
- Numbers k such that (k,k+8) forms a pair of consecutive primes ending respectively in 1 and 9.at n=22A141026