285812881 has 12 divisors (see below), whose sum is σ = 299737060. Its totient is φ = 272511360.

The previous prime is 285812869. The next prime is 285812921. The reversal of 285812881 is 188218582.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 262926225 + 22886656 = 16215^2 + 4784^2 .

It is not a de Polignac number, because 285812881 - 2¹⁵ = 285780113 is a prime.

It is a super-2 number, since 2×285812881² = 163378005891040322, which contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (285812851) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 215701 + ... + 217021.

Almost surely, 2^285812881 is an apocalyptic number.

It is an amenable number.

285812881 is a deficient number, since it is larger than the sum of its proper divisors (13924179).

285812881 is a wasteful number, since it uses less digits than its factorization.

285812881 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1776 (or 1753 counting only the distinct ones).

The product of its digits is 81920, while the sum is 43.

The square root of 285812881 is about 16906.0013308884. The cubic root of 285812881 is about 658.7095085093.

The spelling of 285812881 in words is "two hundred eighty-five million, eight hundred twelve thousand, eight hundred eighty-one".