8419
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 22
- Digital Root
- 4
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 8420
- 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
- 8418
- Möbius Function
- -1
- Radical
- 8419
- 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
- 34
- 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
- 1052
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Eight iterations of Reverse and Add are needed to reach a palindrome.at n=24A015988
- Smallest nontrivial extension of n-th square which is a prime.at n=28A030685
- 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 91.at n=10A031589
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 62 ones.at n=8A031830
- a(n) = smallest number which is not the sum of exactly 1 or a(n-1) earlier terms.at n=18A035334
- a(n) is the smallest prime number k such that k > n*pi(k), where pi(k) denotes the prime counting function.at n=7A038607
- Smallest prime p such that p/pi(p)>=n.at n=7A038623
- Discriminants of imaginary quadratic fields with class number 19 (negated).at n=21A046016
- Primes such that the sum of the factorials of the digits is a perfect square.at n=25A052279
- a(n) = 4*n^2 - 9*n + 6.at n=46A054556
- Primes p such that x^61 = 2 has no solution mod p.at n=19A059230
- Primes p such that |p - q| is a square, where q is the reversal of p.at n=29A059798
- Smallest prime prime(m) such that floor(prime(m)/m) = n.at n=7A062743
- Smallest prime that begins with the n-th square in decimal notation.at n=28A065145
- Numbers which need eight 'Reverse and Add' steps to reach a palindrome.at n=19A065213
- a(n) is smallest prime > 2*a(n-1), a(1) = 13.at n=9A065546
- Primes on axis of Ulam square spiral (with rows ... / 7 8 9 / 6 1 2 / 5 4 3 / ... ) with origin at (1).at n=41A078784
- 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 d-pattern=[4, 6, 2]; short d-string notation of pattern = [462].at n=19A078851
- Smallest prime beginning with digit reversal of n and not included earlier.at n=47A089356
- Primes p=prime(k) such that in binary representation k is a substring of p.at n=12A091021