285997811 has 6 divisors (see below), whose sum is σ = 312058812. Its totient is φ = 259947020.

The previous prime is 285997793. The next prime is 285997849. The reversal of 285997811 is 118799582.

It is not a de Polignac number, because 285997811 - 2¹⁰ = 285996787 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 285997811.

It is not an unprimeable number, because it can be changed into a prime (285997211) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 53540 + ... + 58638.

It is an arithmetic number, because the mean of its divisors is an integer number (52009802).

Almost surely, 2^285997811 is an apocalyptic number.

285997811 is a deficient number, since it is larger than the sum of its proper divisors (26061001).

285997811 is an frugal number, since it uses more digits than its factorization.

285997811 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10209 (or 5110 counting only the distinct ones).

The product of its digits is 362880, while the sum is 50.

The square root of 285997811 is about 16911.4698060222. The cubic root of 285997811 is about 658.8515465281.

The spelling of 285997811 in words is "two hundred eighty-five million, nine hundred ninety-seven thousand, eight hundred eleven".