256120985 has 16 divisors (see below), whose sum is σ = 324584064. Its totient is φ = 193619712.

The previous prime is 256120981. The next prime is 256121023. The reversal of 256120985 is 589021652.

It is a cyclic number.

It is not a de Polignac number, because 256120985 - 2² = 256120981 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256120981) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3872 + ... + 22961.

It is an arithmetic number, because the mean of its divisors is an integer number (20286504).

Almost surely, 2^256120985 is an apocalyptic number.

It is an amenable number.

256120985 is a deficient number, since it is larger than the sum of its proper divisors (68463079).

256120985 is a wasteful number, since it uses less digits than its factorization.

256120985 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 26944.

The product of its (nonzero) digits is 43200, while the sum is 38.

The square root of 256120985 is about 16003.7803346584. The cubic root of 256120985 is about 635.0604319695.

The spelling of 256120985 in words is "two hundred fifty-six million, one hundred twenty thousand, nine hundred eighty-five".