18316685 has 4 divisors (see below), whose sum is σ = 21980028. Its totient is φ = 14653344.

The previous prime is 18316681. The next prime is 18316693. The reversal of 18316685 is 58661381.

It is a happy number.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 58661381 = 67 ⋅875543.

It can be written as a sum of positive squares in 2 ways, for example, as 9572836 + 8743849 = 3094^2 + 2957^2 .

It is a cyclic number.

It is not a de Polignac number, because 18316685 - 2² = 18316681 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (18316681) 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, 1831664 + ... + 1831673.

It is an arithmetic number, because the mean of its divisors is an integer number (5495007).

Almost surely, 2^18316685 is an apocalyptic number.

It is an amenable number.

18316685 is a deficient number, since it is larger than the sum of its proper divisors (3663343).

18316685 is an equidigital number, since it uses as much as digits as its factorization.

18316685 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3663342.

The product of its digits is 34560, while the sum is 38.

The square root of 18316685 is about 4279.7996448432. The cubic root of 18316685 is about 263.6021565354.

The spelling of 18316685 in words is "eighteen million, three hundred sixteen thousand, six hundred eighty-five".