18867985 has 4 divisors (see below), whose sum is σ = 22641588. Its totient is φ = 15094384.

The previous prime is 18867973. The next prime is 18868001. The reversal of 18867985 is 58976881.

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

It can be written as a sum of positive squares in 2 ways, for example, as 5494336 + 13373649 = 2344^2 + 3657^2 .

It is a cyclic number.

It is not a de Polignac number, because 18867985 - 2¹⁵ = 18835217 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1886794 + ... + 1886803.

It is an arithmetic number, because the mean of its divisors is an integer number (5660397).

Almost surely, 2^18867985 is an apocalyptic number.

It is an amenable number.

18867985 is a deficient number, since it is larger than the sum of its proper divisors (3773603).

18867985 is an equidigital number, since it uses as much as digits as its factorization.

18867985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3773602.

The product of its digits is 967680, while the sum is 52.

The square root of 18867985 is about 4343.7293884403. The cubic root of 18867985 is about 266.2207120980.

The spelling of 18867985 in words is "eighteen million, eight hundred sixty-seven thousand, nine hundred eighty-five".