256381636 has 12 divisors (see below), whose sum is σ = 512763328. Its totient is φ = 109877832.

The previous prime is 256381633. The next prime is 256381673. The reversal of 256381636 is 636183652.

256381636 is an admirable number.

It is an alternating number because its digits alternate between even and odd.

It is not an unprimeable number, because it can be changed into a prime (256381633) 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 3 ways as a sum of consecutive naturals, for example, 4578216 + ... + 4578271.

Almost surely, 2^256381636 is an apocalyptic number.

It is an amenable number.

256381636 is a primitive abundant number, since it is smaller than the sum of its proper divisors, none of which is abundant.

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

256381636 is a wasteful number, since it uses less digits than its factorization.

256381636 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9156498 (or 9156496 counting only the distinct ones).

The product of its digits is 155520, while the sum is 40.

The square root of 256381636 is about 16011.9216835457. The cubic root of 256381636 is about 635.2757898482.

The spelling of 256381636 in words is "two hundred fifty-six million, three hundred eighty-one thousand, six hundred thirty-six".