18388836 has 24 divisors (see below), whose sum is σ = 47675040. Its totient is φ = 6129576.

The previous prime is 18388831. The next prime is 18388873. The reversal of 18388836 is 63888381.

It is a junction number, because it is equal to n+sod(n) for n = 18388791 and 18388800.

It is not an unprimeable number, because it can be changed into a prime (18388831) 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 7 ways as a sum of consecutive naturals, for example, 85026 + ... + 85241.

It is an arithmetic number, because the mean of its divisors is an integer number (1986460).

Almost surely, 2^18388836 is an apocalyptic number.

It is an amenable number.

18388836 is an abundant number, since it is smaller than the sum of its proper divisors (29286204).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

18388836 is a wasteful number, since it uses less digits than its factorization.

18388836 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 170280 (or 170272 counting only the distinct ones).

The product of its digits is 221184, while the sum is 45.

The square root of 18388836 is about 4288.2206099966. The cubic root of 18388836 is about 263.9478202658.

The spelling of 18388836 in words is "eighteen million, three hundred eighty-eight thousand, eight hundred thirty-six".