18628985 has 12 divisors (see below), whose sum is σ = 23105124. Its totient is φ = 14418720.

The previous prime is 18628937. The next prime is 18628993. The reversal of 18628985 is 58982681.

It can be written as a sum of positive squares in 2 ways, for example, as 5697769 + 12931216 = 2387^2 + 3596^2 .

It is not a de Polignac number, because 18628985 - 2²⁴ = 1851769 is a prime.

It is a Duffinian 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 11 ways as a sum of consecutive naturals, for example, 2867 + ... + 6743.

It is an arithmetic number, because the mean of its divisors is an integer number (1925427).

Almost surely, 2^18628985 is an apocalyptic number.

It is an amenable number.

18628985 is a deficient number, since it is larger than the sum of its proper divisors (4476139).

18628985 is an equidigital number, since it uses as much as digits as its factorization.

18628985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3944 (or 3913 counting only the distinct ones).

The product of its digits is 276480, while the sum is 47.

The square root of 18628985 is about 4316.1307904187. The cubic root of 18628985 is about 265.0918632507.

The spelling of 18628985 in words is "eighteen million, six hundred twenty-eight thousand, nine hundred eighty-five".