8089
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 25
- Digital Root
- 7
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 1
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 8090
- 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
- 8088
- Möbius Function
- -1
- Radical
- 8089
- 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
- 26
- 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
- 1017
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Pseudo-squares: a(n) = the least nonsquare positive integer which is 1 mod 8 and is a (nonzero) quadratic residue modulo the first n odd primes.at n=5A002189
- Smallest prime p of form p = 8k+1 such that first n primes (p_1=2, ..., p_n) are quadratic residues mod p.at n=5A002224
- Primes that remain prime through 3 iterations of function f(x) = 2x + 5.at n=26A023274
- Primes that remain prime through 4 iterations of function f(x) = 2x + 5.at n=11A023304
- Numbers whose least quadratic nonresidue (A020649) is 17.at n=5A025026
- a(n) is the least odd prime p such that the maximum run length of consecutive quadratic residues modulo p is n.at n=31A025046
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 62 ones.at n=5A031830
- Primes that are decimal concatenations of n with n + 9.at n=13A032632
- Lucky numbers that are concatenations of n with n + 9.at n=9A032659
- Primes with first digit 8.at n=26A045714
- Initial pile sizes that guarantee a win for player 2 in a variant of Fibonacci Nim where the players may not take one stone.at n=38A052492
- Primes having only {0, 6, 8, 9} as digits.at n=8A053580
- Second term of weak prime quintets: p(m)-p(m-1) < p(m+1)-p(m) < p(m+2)-p(m+1) < p(m+3)-p(m+2).at n=19A054824
- Number of ways to cover (without overlapping) a ring lattice (necklace) of n sites with molecules that are 5 sites wide.at n=31A058368
- Primes with 17 as smallest positive primitive root.at n=11A061329
- Primes having only 0,4,6,8,9 as digits.at n=22A061372
- Integers n > 1997 such that the 'Reverse and Add!' trajectory of n joins the trajectory of 1997.at n=5A063055
- a(n) = floor(1/(n-1) * Sum_{k=1..n-1} a(k)^(n/k)), given a(0)=1, a(1)=2, a(2)=6.at n=11A079118
- Prime numbers using only the curved digits 0, 3, 6, 8 and 9.at n=32A079652
- Primes of the form n^2 - 11.at n=15A091272