19109 has 4 divisors (see below), whose sum is σ = 19404. Its totient is φ = 18816.

The previous prime is 19087. The next prime is 19121. The reversal of 19109 is 90191.

19109 is nontrivially palindromic in base 9.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 14884 + 4225 = 122^2 + 65^2 .

It is a cyclic number.

It is not a de Polignac number, because 19109 - 2¹² = 15013 is a prime.

It is a Duffinian number.

19109 is an undulating number in base 14.

It is a Curzon number.

It is a plaindrome in base 15.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19139) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2 + ... + 195.

It is an arithmetic number, because the mean of its divisors is an integer number (4851).

2¹⁹¹⁰⁹ is an apocalyptic number.

It is an amenable number.

19109 is a deficient number, since it is larger than the sum of its proper divisors (295).

19109 is an equidigital number, since it uses as much as digits as its factorization.

19109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 294.

The product of its (nonzero) digits is 81, while the sum is 20.

The square root of 19109 is about 138.2353066333. The cubic root of 19109 is about 26.7349465482.

It can be divided in two parts, 19 and 109, that added together give a 7-th power (128 = 2⁷).

The spelling of 19109 in words is "nineteen thousand, one hundred nine".