18324431 has 4 divisors (see below), whose sum is σ = 18383664. Its totient is φ = 18265200.

The previous prime is 18324403. The next prime is 18324443. The reversal of 18324431 is 13442381.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 18324431 - 2¹⁸ = 18062287 is a prime.

It is a super-2 number, since 2×18324431² = 671569542947522, which contains 22 as substring.

It is a Duffinian number.

It is a plaindrome in base 16.

It is a self number, because there is not a number n which added to its sum of digits gives 18324431.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18324401) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29150 + ... + 29771.

It is an arithmetic number, because the mean of its divisors is an integer number (4595916).

Almost surely, 2^18324431 is an apocalyptic number.

18324431 is a deficient number, since it is larger than the sum of its proper divisors (59233).

18324431 is an equidigital number, since it uses as much as digits as its factorization.

18324431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 59232.

The product of its digits is 2304, while the sum is 26.

The square root of 18324431 is about 4280.7044980937. The cubic root of 18324431 is about 263.6393098111.

The spelling of 18324431 in words is "eighteen million, three hundred twenty-four thousand, four hundred thirty-one".