256388 has 12 divisors (see below), whose sum is σ = 489552. Its totient is φ = 116520.

The previous prime is 256369. The next prime is 256391. The reversal of 256388 is 883652.

256388 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a d-powerful number, because it can be written as 2¹⁴ + 5⁶ + 3¹¹ + 6⁶ + 8² + 8³ .

It is an inconsummate number, since it does not exist a number n which divided by its sum of digits gives 256388.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 2870 + ... + 2957.

It is an arithmetic number, because the mean of its divisors is an integer number (40796).

2²⁵⁶³⁸⁸ is an apocalyptic number.

It is an amenable number.

256388 is a deficient number, since it is larger than the sum of its proper divisors (233164).

256388 is a wasteful number, since it uses less digits than its factorization.

256388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5842 (or 5840 counting only the distinct ones).

The product of its digits is 11520, while the sum is 32.

The square root of 256388 is about 506.3477066207. The cubic root of 256388 is about 63.5281046155.

Subtracting 256388 from its reverse (883652), we obtain a square (627264 = 792²).

The spelling of 256388 in words is "two hundred fifty-six thousand, three hundred eighty-eight".