17659
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 2
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 17660
- 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
- 17658
- Möbius Function
- -1
- Radical
- 17659
- 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
- yes
- Harshad Number
- no
- Narcissistic Number
- no
- Collatz Steps
- 128
- 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
- 2029
- 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) = 7x + 6.at n=24A023290
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 86 ones.at n=15A031854
- Numbers k such that 71*2^k+1 is prime.at n=18A032385
- Odd k for which k+2^m is composite for all m < k.at n=9A033919
- Primes p such that p and p^2 have same digit sum.at n=29A058370
- Primes p such that x^27 = 2 has no solution mod p, but x^9 = 2 has a solution mod p.at n=4A059354
- Minimal Thompson primes: a(n) is the smallest prime expressible as p1*p2*...*pk-q1*q2*...*qj, where k+j=n and {p1,...,qj} are the first n primes.at n=11A060772
- Write product of first n primes as x*y with x<y and x maximal; sequence gives value of y-x.at n=13A061060
- Primes p such that x^9 = 2 has a solution mod p, but x^(9^2) = 2 has no solution mod p.at n=5A070185
- Numbers m such that m! + p is a prime, where p is the smallest prime > m.at n=26A084749
- Twin-prime-indexed primes (TWIPS): members of a pair of twin primes whose prime index is also a member of a pair of twin primes.at n=38A087373
- a(n) = (27*n^2 + 9*n + 2)/2.at n=36A093485
- Centered triangular numbers that are prime.at n=25A125602
- Primes congruent to 10 mod 53.at n=36A142540
- Primes congruent to 18 mod 59.at n=39A142745
- Primes congruent to 30 mod 61.at n=32A142828
- Primes p such that the multiplicative order of 2 modulo p is (p-1)/9.at n=10A152309
- Primes p such that p1 = ceiling(p/2) + p is prime and p2 = floor(p1/2) + p1 is prime.at n=37A158714
- a(n)=sqrt((A173631(n))^2-4*P_n), where P_n is product of first n primes, if this value is integral and a(n)=0, otherwise.at n=14A173632
- Primes p such that p plus or minus the sum of its digits squared yields a prime in both cases.at n=38A179550