285808 has 10 divisors (see below), whose sum is σ = 553784. Its totient is φ = 142896.

The previous prime is 285781. The next prime is 285823. The reversal of 285808 is 808582.

It is a self number, because there is not a number n which added to its sum of digits gives 285808.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 8916 + ... + 8947.

2²⁸⁵⁸⁰⁸ is an apocalyptic number.

It is an amenable number.

285808 is a deficient number, since it is larger than the sum of its proper divisors (267976).

285808 is a wasteful number, since it uses less digits than its factorization.

285808 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 17871 (or 17865 counting only the distinct ones).

The product of its (nonzero) digits is 5120, while the sum is 31.

The square root of 285808 is about 534.6101383251. The cubic root of 285808 is about 65.8705758761.

The spelling of 285808 in words is "two hundred eighty-five thousand, eight hundred eight".