8231
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 14
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 8232
- 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
- 8230
- Möbius Function
- -1
- Radical
- 8231
- 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
- 52
- 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
- 1032
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Smallest prime p such that the product of q/(q-1) over the primes from prime(n) to p is greater than 2.at n=22A001275
- Number of positions in game "Connect Four" (played on usual 6-row, 7-column board) after n moves, up to reflection.at n=6A013582
- Numbers k such that the continued fraction for sqrt(k) has period 72.at n=32A020411
- a(n+1) = [ A*a(n)+B ]/p^r, where p^r is the highest power of p diving [ A*a(n)+B ] and p=2, A=2.00013, B=3.0.at n=32A029580
- 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 89.at n=31A031587
- Denominators of continued fraction convergents to sqrt(421).at n=11A041801
- Primes with first digit 8.at n=41A045714
- Sequence of 2 Pythagorean triangles, each with a leg and hypotenuse prime. The leg of the second triangle is the hypotenuse of the first.at n=30A048270
- Values of A (the short leg) of a Pythagorean triangle with A and C (the hypotenuse) both prime and part of a twin prime.at n=24A051642
- Primes at which the difference pattern X24Y (X and Y >= 6) occurs in A001223.at n=19A052163
- First term of weak prime quintets: p(m+1)-p(m) < p(m+2)-p(m+1) < p(m+3)-p(m+2) < p(m+4)-p(m+3).at n=21A054823
- Primes q of the form q = 10p + 1, where p is also prime.at n=33A055781
- Primes with 11 as smallest positive primitive root.at n=35A061324
- Partial sums of A035282.at n=46A078472
- Initial term in sequence of four consecutive primes separated by 3 consecutive differences each <= 6 (i.e., when d = 2, 4 or 6) and forming pattern = [2, 4, 6]; short notation = [246] d-pattern.at n=18A078847
- Least k such that the class number of quadratic order of discriminant D=-4k equals p, where p runs through the primes.at n=27A079029
- Primes p such that 7 is the largest of all prime factors of the numbers between p and the next prime (cf. A052248).at n=13A080186
- Recursive binary interleaving code for rooted plane binary trees, as ordered by A014486.at n=41A082856
- a(n) = 2^n + 3*n.at n=12A086653
- Lower twin primes with lower twin prime index.at n=12A088460