256781604 has 12 divisors (see below), whose sum is σ = 599157104. Its totient is φ = 85593864.

The previous prime is 256781597. The next prime is 256781621. The reversal of 256781604 is 406187652.

256781604 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (12).

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, 10699222 + ... + 10699245.

Almost surely, 2^256781604 is an apocalyptic number.

It is an amenable number.

256781604 is an abundant number, since it is smaller than the sum of its proper divisors (342375500).

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

256781604 is a wasteful number, since it uses less digits than its factorization.

256781604 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21398474 (or 21398472 counting only the distinct ones).

The product of its (nonzero) digits is 80640, while the sum is 39.

The square root of 256781604 is about 16024.4065100708. The cubic root of 256781604 is about 635.6059720647.

The spelling of 256781604 in words is "two hundred fifty-six million, seven hundred eighty-one thousand, six hundred four".