256656120205 has 16 divisors (see below), whose sum is σ = 317654555904. Its totient is φ = 198966596800.

The previous prime is 256656120163. The next prime is 256656120239. The reversal of 256656120205 is 502021656652.

It is not a de Polignac number, because 256656120205 - 2⁹ = 256656119693 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 5382967 + ... + 5430436.

It is an arithmetic number, because the mean of its divisors is an integer number (19853409744).

Almost surely, 2^256656120205 is an apocalyptic number.

It is an amenable number.

256656120205 is a deficient number, since it is larger than the sum of its proper divisors (60998435699).

256656120205 is a wasteful number, since it uses less digits than its factorization.

256656120205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 10813556.

The product of its (nonzero) digits is 216000, while the sum is 40.

Adding to 256656120205 its reverse (502021656652), we get a palindrome (758677776857).

The spelling of 256656120205 in words is "two hundred fifty-six billion, six hundred fifty-six million, one hundred twenty thousand, two hundred five".