18985388 has 12 divisors (see below), whose sum is σ = 33720792. Its totient is φ = 9350880.

The previous prime is 18985387. The next prime is 18985397. The reversal of 18985388 is 88358981.

It is not an unprimeable number, because it can be changed into a prime (18985387) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 35153 + ... + 35688.

It is an arithmetic number, because the mean of its divisors is an integer number (2810066).

Almost surely, 2^18985388 is an apocalyptic number.

It is an amenable number.

18985388 is a deficient number, since it is larger than the sum of its proper divisors (14735404).

18985388 is a wasteful number, since it uses less digits than its factorization.

18985388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 70912 (or 70910 counting only the distinct ones).

The product of its digits is 552960, while the sum is 50.

The square root of 18985388 is about 4357.2225098106. Note that the first 3 decimals coincide. The cubic root of 18985388 is about 266.7717426188.

The spelling of 18985388 in words is "eighteen million, nine hundred eighty-five thousand, three hundred eighty-eight".