18390427 has 16 divisors (see below), whose sum is σ = 20782944. Its totient is φ = 16262400.

The previous prime is 18390403. The next prime is 18390431. The reversal of 18390427 is 72409381.

It is not a de Polignac number, because 18390427 - 2⁷ = 18390299 is a prime.

It is a Duffinian number.

It is a nialpdrome in base 11.

It is a junction number, because it is equal to n+sod(n) for n = 18390392 and 18390401.

It is not an unprimeable number, because it can be changed into a prime (18390467) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 54403 + ... + 54739.

It is an arithmetic number, because the mean of its divisors is an integer number (1298934).

Almost surely, 2^18390427 is an apocalyptic number.

18390427 is a deficient number, since it is larger than the sum of its proper divisors (2392517).

18390427 is an equidigital number, since it uses as much as digits as its factorization.

18390427 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 411 (or 389 counting only the distinct ones).

The product of its (nonzero) digits is 12096, while the sum is 34.

The square root of 18390427 is about 4288.4061141641. The cubic root of 18390427 is about 263.9554322914.

The spelling of 18390427 in words is "eighteen million, three hundred ninety thousand, four hundred twenty-seven".