256661206511444 has 96 divisors (see below), whose sum is σ = 536130859756800. Its totient is φ = 107409281890176.

The previous prime is 256661206511431. The next prime is 256661206511471. The reversal of 256661206511444 is 444115602166652.

256661206511444 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 209237234 + ... + 210460310.

It is an arithmetic number, because the mean of its divisors is an integer number (5584696455800).

Almost surely, 2^{256661206511444} is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256661206511444, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (268065429878400).

256661206511444 is an abundant number, since it is smaller than the sum of its proper divisors (279469653245356).

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

256661206511444 is a wasteful number, since it uses less digits than its factorization.

256661206511444 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1226702 (or 1226686 counting only the distinct ones).

The product of its (nonzero) digits is 8294400, while the sum is 53.

The spelling of 256661206511444 in words is "two hundred fifty-six trillion, six hundred sixty-one billion, two hundred six million, five hundred eleven thousand, four hundred forty-four".