18985291 has 6 divisors (see below), whose sum is σ = 20558220. Its totient is φ = 17524728.

The previous prime is 18985283. The next prime is 18985297. The reversal of 18985291 is 19258981.

It is not a de Polignac number, because 18985291 - 2³ = 18985283 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (18985297) by changing a digit.

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 5 ways as a sum of consecutive naturals, for example, 56001 + ... + 56338.

It is an arithmetic number, because the mean of its divisors is an integer number (3426370).

Almost surely, 2^18985291 is an apocalyptic number.

18985291 is a deficient number, since it is larger than the sum of its proper divisors (1572929).

18985291 is a wasteful number, since it uses less digits than its factorization.

18985291 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 112365 (or 112352 counting only the distinct ones).

The product of its digits is 51840, while the sum is 43.

The square root of 18985291 is about 4357.2113788523. The cubic root of 18985291 is about 266.7712882886.

The spelling of 18985291 in words is "eighteen million, nine hundred eighty-five thousand, two hundred ninety-one".