256521055072 has 24 divisors (see below), whose sum is σ = 507563658000. Its totient is φ = 127615999104.

The previous prime is 256521055061. The next prime is 256521055081. The reversal of 256521055072 is 270550125652.

It is a congruent number.

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, 20135047 + ... + 20147782.

It is an arithmetic number, because the mean of its divisors is an integer number (21148485750).

Almost surely, 2^256521055072 is an apocalyptic number.

It is an amenable number.

256521055072 is a deficient number, since it is larger than the sum of its proper divisors (251042602928).

256521055072 is a wasteful number, since it uses less digits than its factorization.

256521055072 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 40283038 (or 40283030 counting only the distinct ones).

The product of its (nonzero) digits is 210000, while the sum is 40.

The spelling of 256521055072 in words is "two hundred fifty-six billion, five hundred twenty-one million, fifty-five thousand, seventy-two".