18229985 has 4 divisors (see below), whose sum is σ = 21875988. Its totient is φ = 14583984.

The previous prime is 18229973. The next prime is 18229999. The reversal of 18229985 is 58992281.

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 7054336 + 11175649 = 2656^2 + 3343^2 .

It is a cyclic number.

It is not a de Polignac number, because 18229985 - 2⁴ = 18229969 is a prime.

It is a Duffinian number.

It is a Curzon 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, 1822994 + ... + 1823003.

It is an arithmetic number, because the mean of its divisors is an integer number (5468997).

Almost surely, 2^18229985 is an apocalyptic number.

It is an amenable number.

18229985 is a deficient number, since it is larger than the sum of its proper divisors (3646003).

18229985 is an equidigital number, since it uses as much as digits as its factorization.

18229985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3646002.

The product of its digits is 103680, while the sum is 44.

The square root of 18229985 is about 4269.6586514615. The cubic root of 18229985 is about 263.1855880435.

The spelling of 18229985 in words is "eighteen million, two hundred twenty-nine thousand, nine hundred eighty-five".