18387685 has 4 divisors (see below), whose sum is σ = 22065228. Its totient is φ = 14710144.

The previous prime is 18387679. The next prime is 18387701. The reversal of 18387685 is 58678381.

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 2563201 + 15824484 = 1601^2 + 3978^2 .

It is a cyclic number.

It is not a de Polignac number, because 18387685 - 2¹⁹ = 17863397 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1838764 + ... + 1838773.

It is an arithmetic number, because the mean of its divisors is an integer number (5516307).

Almost surely, 2^18387685 is an apocalyptic number.

It is an amenable number.

18387685 is a deficient number, since it is larger than the sum of its proper divisors (3677543).

18387685 is an equidigital number, since it uses as much as digits as its factorization.

18387685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3677542.

The product of its digits is 322560, while the sum is 46.

The square root of 18387685 is about 4288.0864030474. The cubic root of 18387685 is about 263.9423131150.

The spelling of 18387685 in words is "eighteen million, three hundred eighty-seven thousand, six hundred eighty-five".