18000431 has 4 divisors (see below), whose sum is σ = 18009264. Its totient is φ = 17991600.

The previous prime is 18000407. The next prime is 18000439. The reversal of 18000431 is 13400081.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It is a cyclic number.

It is not a de Polignac number, because 18000431 - 2¹⁰ = 17999407 is a prime.

It is a super-2 number, since 2×18000431² = 648031032371522, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18000439) 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, 371 + ... + 6011.

It is an arithmetic number, because the mean of its divisors is an integer number (4502316).

Almost surely, 2^18000431 is an apocalyptic number.

18000431 is a deficient number, since it is larger than the sum of its proper divisors (8833).

18000431 is an equidigital number, since it uses as much as digits as its factorization.

18000431 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8832.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 18000431 is about 4242.6914806523. The cubic root of 18000431 is about 262.0762311441.

The spelling of 18000431 in words is "eighteen million, four hundred thirty-one", and thus it is an aban number.