285680256 has 64 divisors (see below), whose sum is σ = 779386080. Its totient is φ = 92648448.

The previous prime is 285680243. The next prime is 285680281. The reversal of 285680256 is 652086582.

It is a tau number, because it is divible by the number of its divisors (64).

It is a super-2 number, since 2×285680256² = 163226417336451072, which contains 22 as substring.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 4155 + ... + 24261.

Almost surely, 2^285680256 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 285680256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (389693040).

285680256 is an abundant number, since it is smaller than the sum of its proper divisors (493705824).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

285680256 is a wasteful number, since it uses less digits than its factorization.

285680256 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 20161 (or 20149 counting only the distinct ones).

The product of its (nonzero) digits is 230400, while the sum is 42.

The square root of 285680256 is about 16902.0784520721. The cubic root of 285680256 is about 658.6076063319.

The spelling of 285680256 in words is "two hundred eighty-five million, six hundred eighty thousand, two hundred fifty-six".