256217558116 has 24 divisors (see below), whose sum is σ = 495922138040. Its totient is φ = 115058195712.

The previous prime is 256217558087. The next prime is 256217558137. The reversal of 256217558116 is 611855712652.

It can be written as a sum of positive squares in 4 ways, for example, as 15385921600 + 240831636516 = 124040^2 + 490746^2 .

It is a self number, because there is not a number n which added to its sum of digits gives 256217558116.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 66582681 + ... + 66586528.

Almost surely, 2^256217558116 is an apocalyptic number.

256217558116 is a gapful number since it is divisible by the number (26) formed by its first and last digit.

It is an amenable number.

256217558116 is a deficient number, since it is larger than the sum of its proper divisors (239704579924).

256217558116 is a wasteful number, since it uses less digits than its factorization.

256217558116 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 133169263 (or 133169261 counting only the distinct ones).

The product of its digits is 1008000, while the sum is 49.

The spelling of 256217558116 in words is "two hundred fifty-six billion, two hundred seventeen million, five hundred fifty-eight thousand, one hundred sixteen".