256257617 has 32 divisors (see below), whose sum is σ = 339655680. Its totient is φ = 187289280.

The previous prime is 256257613. The next prime is 256257629. The reversal of 256257617 is 716752652.

256257617 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a cyclic number.

It is not a de Polignac number, because 256257617 - 2² = 256257613 is a prime.

It is not an unprimeable number, because it can be changed into a prime (256257613) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 155723 + ... + 157359.

It is an arithmetic number, because the mean of its divisors is an integer number (10614240).

Almost surely, 2^256257617 is an apocalyptic number.

It is an amenable number.

256257617 is a deficient number, since it is larger than the sum of its proper divisors (83398063).

256257617 is a wasteful number, since it uses less digits than its factorization.

256257617 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1781.

The product of its digits is 176400, while the sum is 41.

The square root of 256257617 is about 16008.0485069230. The cubic root of 256257617 is about 635.1733397449.

The spelling of 256257617 in words is "two hundred fifty-six million, two hundred fifty-seven thousand, six hundred seventeen".