285985391 has 16 divisors (see below), whose sum is σ = 295434720. Its totient is φ = 276756480.

The previous prime is 285985387. The next prime is 285985433. The reversal of 285985391 is 193589582.

It is a cyclic number.

It is not a de Polignac number, because 285985391 - 2² = 285985387 is a prime.

It is a Smith number, since the sum of its digits (50) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (285985361) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1355276 + ... + 1355486.

It is an arithmetic number, because the mean of its divisors is an integer number (18464670).

Almost surely, 2^285985391 is an apocalyptic number.

285985391 is a deficient number, since it is larger than the sum of its proper divisors (9449329).

285985391 is a wasteful number, since it uses less digits than its factorization.

285985391 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 554.

The product of its digits is 777600, while the sum is 50.

The square root of 285985391 is about 16911.1025956323. The cubic root of 285985391 is about 658.8420090953.

The spelling of 285985391 in words is "two hundred eighty-five million, nine hundred eighty-five thousand, three hundred ninety-one".