18128439 has 24 divisors (see below), whose sum is σ = 31229952. Its totient is φ = 9907920.

The previous prime is 18128419. The next prime is 18128441. The reversal of 18128439 is 93482181.

It is not a de Polignac number, because 18128439 - 2⁷ = 18128311 is a prime.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18128419) 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 23 ways as a sum of consecutive naturals, for example, 4807 + ... + 7704.

It is an arithmetic number, because the mean of its divisors is an integer number (1301248).

Almost surely, 2^18128439 is an apocalyptic number.

18128439 is a deficient number, since it is larger than the sum of its proper divisors (13101513).

18128439 is a wasteful number, since it uses less digits than its factorization.

18128439 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 12547 (or 12544 counting only the distinct ones).

The product of its digits is 13824, while the sum is 36.

The square root of 18128439 is about 4257.7504623921. The cubic root of 18128439 is about 262.6960059889.

The spelling of 18128439 in words is "eighteen million, one hundred twenty-eight thousand, four hundred thirty-nine".