8999
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 35
- Digital Root
- 8
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 9000
- 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
- 8998
- Möbius Function
- -1
- Radical
- 8999
- 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
- 184
- 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
- yes
- Mersenne Prime
- no
- Sophie Germain Prime
- no
- Safe Prime
- no
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 1117
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes that contain digits 8 and 9 only.at n=1A020472
- 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 93.at n=30A031591
- Numbers k such that the decimal expansion of k! begins with k.at n=6A033147
- Decimal part of cube root of a(n) starts with 8: first term of runs.at n=19A034134
- Smallest n-digit prime containing only the digits 8 and 9, or 0 if no such prime exists.at n=3A036951
- Denominators of continued fraction convergents to sqrt(437).at n=6A041833
- Numbers having three 9's in base 10.at n=8A043527
- Consider the Diophantine equation x^3 + y^3 = z^3 - 1 (x < y < z) or 'Fermat near misses'. Arrange solutions by increasing values of z. Sequence gives values of x.at n=37A050788
- Primes whose digits are composite; primes having only {4, 6, 8, 9} as digits.at n=18A051416
- Smallest number whose sum of digits is n.at n=35A051885
- Primes having only {0, 6, 8, 9} as digits.at n=14A053580
- a(n) = smallest prime q of form q=-1+(p+1)*10^w, where p is n-th prime, or 0 if there is no such prime.at n=23A055785
- Numbers k such that k^16 == 1 (mod 17^3).at n=26A056088
- Near-repdigit primes such that all digits are equal except for an end-digit.at n=50A056710
- Primes of the form 4*k^2 + 163.at n=40A057604
- a(1) = 2; a(n+1) is obtained by trying to change just one digit of a(n), starting with the least significant digit, until a new prime is reached. Take the lexicographically earliest sequence. Digits may be replaced by any larger digit.at n=16A059498
- Primes p such that p^10 reversed is also prime.at n=36A059703
- Primes of the form abbbbb... where a and b are digits.at n=51A061022
- Primes at which sum of digits strictly increases.at n=20A061248
- Primes having only 0,4,6,8,9 as digits.at n=29A061372