256505601 has 24 divisors (see below), whose sum is σ = 377430592. Its totient is φ = 154836000.

The previous prime is 256505581. The next prime is 256505603. The reversal of 256505601 is 106505652.

It is not a de Polignac number, because 256505601 - 2⁵ = 256505569 is a prime.

It is not an unprimeable number, because it can be changed into a prime (256505603) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 99276 + ... + 101826.

Almost surely, 2^256505601 is an apocalyptic number.

It is an amenable number.

256505601 is a deficient number, since it is larger than the sum of its proper divisors (120924991).

256505601 is a wasteful number, since it uses less digits than its factorization.

256505601 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2853 (or 2842 counting only the distinct ones).

The product of its (nonzero) digits is 9000, while the sum is 30.

The square root of 256505601 is about 16015.7922376634. The cubic root of 256505601 is about 635.3781623313.

The spelling of 256505601 in words is "two hundred fifty-six million, five hundred five thousand, six hundred one".