17239
domain: N
Properties
Digital Properties
- Digit Count
- 5
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 5
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 17240
- 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
- 17238
- Möbius Function
- -1
- Radical
- 17239
- 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
- 141
- 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
- 1985
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- a(n+1) = 1 + a( floor(n/1) ) + a( floor(n/2) ) + ... + a( floor(n/n) ).at n=45A003318
- Supersingular primes of the elliptic curve X_0 (11).at n=20A006962
- Numbers k such that k^2 is palindromic in base 4.at n=24A029986
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 88 ones.at n=18A031856
- Primes with multiplicative persistence value 5.at n=35A046505
- The first of two consecutive primes with equal digital sums.at n=41A066540
- Prime(n) and prime(n+3) use the same digits.at n=20A069795
- a(n) = prime(2*n*(n+1)+1).at n=31A078746
- Smallest number k such that M(n)^2-k*M(n)-1 is prime with M(n) = Mersenne primes = A000668(n).at n=17A139424
- Smallest prime p such that M(n)^2-p*M(n)-1 is prime with M(n)= Mersenne primes =A000668(n).at n=16A139428
- Primes of the form 55x^2+10xy+199y^2.at n=31A140632
- Primes congruent to 14 mod 53.at n=37A142544
- Primes congruent to 11 mod 59.at n=33A142738
- Primes congruent to 37 mod 61.at n=32A142835
- Let N(p,i) denote the result of applying "nextprime" i times to p; a(n) = smallest prime p such that N(p,2) - p = 2*n, or -1 if no such prime exists.at n=25A144103
- Primes p such that p and p+18 are consecutive primes with equal digital sum.at n=40A209875
- Power floor-ceiling sequence of 2+sqrt(2).at n=7A214996
- a(0)=0, a(1)=1, a(n)=min{3 a(k) + 2^(n-k)-1, k=0..(n-1)} for n>=2.at n=46A259823
- Centered 13-gonal (or tridecagonal) primes.at n=9A262493
- a(1) = 2; a(n + 1) = smallest prime > a(n) such that a(n + 1) - a(n) is the product of 7 primes.at n=25A285692