18841389 has 32 divisors (see below), whose sum is σ = 30792960. Its totient is φ = 10002432.

The previous prime is 18841367. The next prime is 18841391. The reversal of 18841389 is 98314881.

It is not a de Polignac number, because 18841389 - 2⁵ = 18841357 is a prime.

It is a Curzon number.

It is a self number, because there is not a number n which added to its sum of digits gives 18841389.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18841189) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 31477 + ... + 32069.

It is an arithmetic number, because the mean of its divisors is an integer number (962280).

Almost surely, 2^18841389 is an apocalyptic number.

It is an amenable number.

18841389 is a deficient number, since it is larger than the sum of its proper divisors (11951571).

18841389 is a wasteful number, since it uses less digits than its factorization.

18841389 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 709.

The product of its digits is 55296, while the sum is 42.

The square root of 18841389 is about 4340.6668842472. Note that the first 3 decimals coincide. The cubic root of 18841389 is about 266.0955665057.

The spelling of 18841389 in words is "eighteen million, eight hundred forty-one thousand, three hundred eighty-nine".