18388428 has 24 divisors (see below), whose sum is σ = 45165120. Its totient is φ = 5806800.

The previous prime is 18388427. The next prime is 18388429. The reversal of 18388428 is 82488381.

It is an interprime number because it is at equal distance from previous prime (18388427) and next prime (18388429).

It is a super-2 number, since 2×18388428² = 676268568622368, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 18388428.

It is not an unprimeable number, because it can be changed into a prime (18388427) 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, 40098 + ... + 40553.

It is an arithmetic number, because the mean of its divisors is an integer number (1881880).

Almost surely, 2^18388428 is an apocalyptic number.

It is an amenable number.

18388428 is an abundant number, since it is smaller than the sum of its proper divisors (26776692).

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

18388428 is a wasteful number, since it uses less digits than its factorization.

18388428 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 80677 (or 80675 counting only the distinct ones).

The product of its digits is 98304, while the sum is 42.

The square root of 18388428 is about 4288.1730375534. The cubic root of 18388428 is about 263.9458681483.

The spelling of 18388428 in words is "eighteen million, three hundred eighty-eight thousand, four hundred twenty-eight".