8831
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 20
- Digital Root
- 2
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 3
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 8832
- 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
- 8830
- Möbius Function
- -1
- Radical
- 8831
- 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
- 122
- 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
- 1100
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes that remain prime through 3 iterations of function f(x) = 4x + 3.at n=24A023281
- Primes of form k^2 - 5.at n=22A028877
- 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=16A031591
- a(n) = prime(100*n).at n=10A031921
- Primes p from A031924 such that A052180(primepi(p)) = 11.at n=20A052232
- Primes q of the form q = 10p + 1, where p is also prime.at n=35A055781
- Primes p with the following property: let d_1, d_2, ... be the distinct digits occurring in the decimal expansion of p. Then for each d_i, dropping all the digits d_i from p produces a prime number. Leading 0's are not allowed.at n=40A057876
- Primes with 3 distinct digits that remain prime (no leading zeros allowed) after deleting all occurrences of any one of its distinct digits.at n=30A057879
- Numbers n such that 1n1, 3n3, 7n7 and 9n9 are all primes.at n=21A059677
- Primes p such that 1p1, 3p3, 7p7 and 9p9 are all primes.at n=5A059694
- Irregular primes with irregularity index three.at n=14A060975
- a(n) = k such that the k-th triangular number is A068808(n).at n=22A067991
- Lonely non-twin primes: non-twins sandwiched between two pairs of twins.at n=33A068016
- Denominator(Bernoulli(n-1) + 1/n)=66, where n runs through the primes.at n=39A090799
- Related to A097871.at n=3A097993
- Prime numbers p such that the concatenation of all odd primes up through p in decreasing order is prime.at n=5A100003
- Smallest prime a such that (a*b)^2 + a*b -1 is prime with b prime = 2^(2*n) - 2^n - 1, see A098845 for n.at n=21A107639
- Primes in A112714.at n=36A112715
- Smallest prime of the form: all eights followed by prime(n). a(n)> prime(n). 0 if no such prime exists.at n=10A113890
- Number of integer-sided triangles with all sides <= n and sides relatively prime.at n=48A123324