18381472 has 24 divisors (see below), whose sum is σ = 36481536. Its totient is φ = 9116352.

The previous prime is 18381469. The next prime is 18381491. The reversal of 18381472 is 27418381.

It is a happy number.

It is a Smith number, since the sum of its digits (34) coincides with the sum of the digits of its prime factors.

It is an alternating number because its digits alternate between odd and even.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1803 + ... + 6325.

It is an arithmetic number, because the mean of its divisors is an integer number (1520064).

Almost surely, 2^18381472 is an apocalyptic number.

It is an amenable number.

18381472 is a deficient number, since it is larger than the sum of its proper divisors (18100064).

18381472 is a wasteful number, since it uses less digits than its factorization.

18381472 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4660 (or 4652 counting only the distinct ones).

The product of its digits is 10752, while the sum is 34.

The square root of 18381472 is about 4287.3618928194. The cubic root of 18381472 is about 263.9125820147.

The spelling of 18381472 in words is "eighteen million, three hundred eighty-one thousand, four hundred seventy-two".