9199
domain: N
Properties
Digital Properties
- Digit Count
- 4
- Digit Sum
- 28
- Digital Root
- 1
- Palindromic Number
- no
- Repdigit
- no
- Automorphic
- no
- Kaprekar Number
- no
- Multiplicative Persistence
- 4
Divisibility
- Divisor Count
- 2
- Divisor Sum
- 9200
- 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
- 9198
- Möbius Function
- -1
- Radical
- 9199
- 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
- 65
- 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
- 1140
- Perfect Power
- no
- Smooth Number
- no
- Carmichael Number
- no
Classification
- Even
- no
- Odd
- yes
Appears in sequences
- Primes that contain digits 1 and 9 only.at n=8A020457
- Primes that remain prime through 3 iterations of function f(x) = 7x + 6.at n=16A023290
- Smallest nontrivial extension of n-th palindromic prime which is a prime.at n=18A030680
- 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 95.at n=15A031593
- Numbers k such that the period of the continued fraction for sqrt(k) contains exactly 78 ones.at n=4A031846
- Primes that are concatenations of n with n + 8.at n=10A032631
- Number of partitions of n with equal number of parts congruent to each of 0 and 2 (mod 3).at n=44A035535
- Positive numbers having the same set of digits in base 7 and base 9.at n=45A037439
- Numbers having three 9's in base 10.at n=10A043527
- Numbers whose base-4 representation contains exactly two 2's and four 3's.at n=32A045147
- Primes with first digit 9.at n=37A045715
- a(n) = A047980(2n).at n=26A047981
- Primes whose sum of digits is the perfect number 28.at n=22A048517
- Primes containing only two distinct digits whose sum of digits is 28, the second perfect number.at n=1A048518
- Primes p such that number of primes produced according to rules stipulated in Honaker's A048853 is 2.at n=3A050664
- Prime number spiral (clockwise, East spoke).at n=17A054555
- First member of a prime triple in a 2p-1 progression.at n=41A057326
- Primes p such that p and p^2 have same digit sum.at n=18A058370
- Prime having only {0, 1, 4, 9} as digits.at n=45A061246
- Primes starting and ending with 9.at n=6A062335