16187
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 23
- Digital Root
- 5
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 16188
- Proper Divisor Sum (Aliquot Sum)
- 1
- Abundant Number
- no
- Perfect Number
- no
- Deficient Number
- yes
- Weird Number
- no
- Untouchable Number
- no
- Primitive Abundant
- no
Derived Values
- Euler's Totient
- 16186
- Möbius Function
- -1
- Radical
- 16187
- 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
- 159
- 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
- yes
- Powerful Number
- no
- Achilles Number
- no
- Prime Index
- 1881
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Coordination sequence for sigma-CrFe, Position Xb.at n=32A009960
- Primes that remain prime through 2 iterations of function f(x) = 8x + 1.at n=32A023260
- Primes that remain prime through 3 iterations of function f(x) = 8x + 1.at n=6A023291
- a(0) = 1; a(n) = 2*n*a(n-1) - 1 for n >= 1.at n=6A055214
- Gives an LCD representation of n.at n=36A071843
- Safe primes (A005385) (p and (p-1)/2 are primes) such that 8*p+1 (A023228) is also prime.at n=38A075706
- Smallest member of a pair of consecutive twin prime pairs that have three primes between them.at n=20A089635
- Primes p = prime(k) such that both p+2 and prime(k+6)-2 are prime numbers.at n=37A105413
- Larger prime in pair prime(k) +/- k for some k.at n=24A107637
- Primes p such that little googol - p is prime.at n=35A108256
- A variation on Flavius's sieves (A000960, A099207): Start with the Chen primes; at the k-th sieving step, remove every (k+1)-st term of the sequence remaining after the (k-1)-st sieving step; iterate.at n=34A118500
- Primes of the form 210k + 17.at n=37A140842
- Primes congruent to 19 mod 47.at n=37A142370
- Primes congruent to 22 mod 53.at n=33A142552
- Primes congruent to 21 mod 59.at n=33A142748
- Primes congruent to 22 mod 61.at n=32A142820
- Irregular table with first row containing the single term 3; in the n-th row, n>=2, we list in increasing order those d=2^(n+1)-a, for each term a in all the preceding rows, such that d is prime.at n=35A152871
- Primes of the form 2*p+1 where p is prime and p+1 is squarefree.at n=39A153209
- Primes p such that p + 2, p + 6, and the concatenation p (p+2) (p+6) is prime.at n=6A174858
- Number of Dyck n-paths all of whose ascents and descents have lengths equal to 1 (mod 10).at n=38A212369