256138667844 has 12 divisors (see below), whose sum is σ = 597656891664. Its totient is φ = 85379555944.

The previous prime is 256138667749. The next prime is 256138667857. The reversal of 256138667844 is 448766831652.

It is a happy number.

256138667844 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is a tau number, because it is divible by the number of its divisors (12).

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, 10672444482 + ... + 10672444505.

It is an arithmetic number, because the mean of its divisors is an integer number (49804740972).

Almost surely, 2^256138667844 is an apocalyptic number.

It is an amenable number.

256138667844 is an abundant number, since it is smaller than the sum of its proper divisors (341518223820).

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

256138667844 is a wasteful number, since it uses less digits than its factorization.

256138667844 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 21344888994 (or 21344888992 counting only the distinct ones).

The product of its digits is 46448640, while the sum is 60.

The spelling of 256138667844 in words is "two hundred fifty-six billion, one hundred thirty-eight million, six hundred sixty-seven thousand, eight hundred forty-four".