18512985 has 16 divisors (see below), whose sum is σ = 29756736. Its totient is φ = 9828288.

The previous prime is 18512981. The next prime is 18513023. The reversal of 18512985 is 58921581.

It is not a de Polignac number, because 18512985 - 2² = 18512981 is a prime.

It is a super-2 number, since 2×18512985² = 685461227220450, which contains 22 as substring.

It is not an unprimeable number, because it can be changed into a prime (18512981) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 687 + ... + 6123.

It is an arithmetic number, because the mean of its divisors is an integer number (1859796).

Almost surely, 2^18512985 is an apocalyptic number.

18512985 is a gapful number since it is divisible by the number (15) formed by its first and last digit.

It is an amenable number.

18512985 is a deficient number, since it is larger than the sum of its proper divisors (11243751).

18512985 is a wasteful number, since it uses less digits than its factorization.

18512985 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5672.

The product of its digits is 28800, while the sum is 39.

The square root of 18512985 is about 4302.6718443311. The cubic root of 18512985 is about 264.5404876302.

The spelling of 18512985 in words is "eighteen million, five hundred twelve thousand, nine hundred eighty-five".