256218135688278 has 48 divisors (see below), whose sum is σ = 574299807868800. Its totient is φ = 82458456218880.

The previous prime is 256218135688261. The next prime is 256218135688301. The reversal of 256218135688278 is 872886531812652.

256218135688278 is a `hidden beast` number, since 2 + 5 + 6 + 21 + 8 + 13 + 568 + 8 + 27 + 8 = 666.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 9314683 + ... + 24478553.

It is an arithmetic number, because the mean of its divisors is an integer number (11964579330600).

Almost surely, 2^{256218135688278} is an apocalyptic number.

256218135688278 is an abundant number, since it is smaller than the sum of its proper divisors (318081672180522).

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

256218135688278 is a wasteful number, since it uses less digits than its factorization.

256218135688278 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 15196277 (or 15196274 counting only the distinct ones).

The product of its digits is 619315200, while the sum is 72.

The spelling of 256218135688278 in words is "two hundred fifty-six trillion, two hundred eighteen billion, one hundred thirty-five million, six hundred eighty-eight thousand, two hundred seventy-eight".