18380331 has 16 divisors (see below), whose sum is σ = 27434400. Its totient is φ = 12161664.

The previous prime is 18380309. The next prime is 18380339. The reversal of 18380331 is 13308381.

It is not a de Polignac number, because 18380331 - 2⁷ = 18380203 is a prime.

It is a super-2 number, since 2×18380331² = 675673135339122, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (27).

It is a junction number, because it is equal to n+sod(n) for n = 18380295 and 18380304.

It is not an unprimeable number, because it can be changed into a prime (18380339) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1215 + ... + 6183.

It is an arithmetic number, because the mean of its divisors is an integer number (1714650).

Almost surely, 2^18380331 is an apocalyptic number.

18380331 is a deficient number, since it is larger than the sum of its proper divisors (9054069).

18380331 is a wasteful number, since it uses less digits than its factorization.

18380331 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5115 (or 5109 counting only the distinct ones).

The product of its (nonzero) digits is 1728, while the sum is 27.

The square root of 18380331 is about 4287.2288252436. The cubic root of 18380331 is about 263.9071212535.

The spelling of 18380331 in words is "eighteen million, three hundred eighty thousand, three hundred thirty-one".