256386340 has 24 divisors (see below), whose sum is σ = 615327552. Its totient is φ = 87903840.

The previous prime is 256386331. The next prime is 256386341. The reversal of 256386340 is 43683652.

It is a self number, because there is not a number n which added to its sum of digits gives 256386340.

It is not an unprimeable number, because it can be changed into a prime (256386341) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 915526 + ... + 915805.

It is an arithmetic number, because the mean of its divisors is an integer number (25638648).

Almost surely, 2^256386340 is an apocalyptic number.

256386340 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

256386340 is an abundant number, since it is smaller than the sum of its proper divisors (358941212).

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

256386340 is a wasteful number, since it uses less digits than its factorization.

256386340 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1831347 (or 1831345 counting only the distinct ones).

The product of its (nonzero) digits is 103680, while the sum is 37.

The square root of 256386340 is about 16012.0685734230. The cubic root of 256386340 is about 635.2796750966.

The spelling of 256386340 in words is "two hundred fifty-six million, three hundred eighty-six thousand, three hundred forty".