18087643 has 12 divisors (see below), whose sum is σ = 21961552. Its totient is φ = 14590080.

The previous prime is 18087613. The next prime is 18087647. The reversal of 18087643 is 34678081.

It is a happy number.

It is not a de Polignac number, because 18087643 - 2⁵ = 18087611 is a prime.

It is a hoax number, since the sum of its digits (37) coincides with the sum of the digits of its distinct prime factors.

It is not an unprimeable number, because it can be changed into a prime (18087647) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2448 + ... + 6493.

Almost surely, 2^18087643 is an apocalyptic number.

18087643 is a deficient number, since it is larger than the sum of its proper divisors (3873909).

18087643 is an equidigital number, since it uses as much as digits as its factorization.

18087643 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 8982 (or 8965 counting only the distinct ones).

The product of its (nonzero) digits is 32256, while the sum is 37.

The square root of 18087643 is about 4252.9569713318. The cubic root of 18087643 is about 262.4988021109.

The spelling of 18087643 in words is "eighteen million, eighty-seven thousand, six hundred forty-three".