18128109 has 16 divisors (see below), whose sum is σ = 26066880. Its totient is φ = 11168640.

The previous prime is 18128101. The next prime is 18128111. The reversal of 18128109 is 90182181.

It is not a de Polignac number, because 18128109 - 2³ = 18128101 is a prime.

It is a Curzon number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18128101) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1542 + ... + 6215.

It is an arithmetic number, because the mean of its divisors is an integer number (1629180).

Almost surely, 2^18128109 is an apocalyptic number.

18128109 is a gapful number since it is divisible by the number (19) formed by its first and last digit.

It is an amenable number.

18128109 is a deficient number, since it is larger than the sum of its proper divisors (7938771).

18128109 is a wasteful number, since it uses less digits than its factorization.

18128109 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 7820.

The product of its (nonzero) digits is 1152, while the sum is 30.

The square root of 18128109 is about 4257.7117093575. The cubic root of 18128109 is about 262.6944119887.

The spelling of 18128109 in words is "eighteen million, one hundred twenty-eight thousand, one hundred nine".