1256558401 has 12 divisors (see below), whose sum is σ = 1483531248. Its totient is φ = 1060971912.

The previous prime is 1256558399. The next prime is 1256558411. The reversal of 1256558401 is 1048556521.

It is not a de Polignac number, because 1256558401 - 2¹ = 1256558399 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1256558411) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 188091 + ... + 194656.

It is an arithmetic number, because the mean of its divisors is an integer number (123627604).

Almost surely, 2^1256558401 is an apocalyptic number.

It is an amenable number.

1256558401 is a deficient number, since it is larger than the sum of its proper divisors (226972847).

1256558401 is an equidigital number, since it uses as much as digits as its factorization.

1256558401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 382828 (or 382821 counting only the distinct ones).

The product of its (nonzero) digits is 48000, while the sum is 37.

The square root of 1256558401 is about 35447.9675157829. The cubic root of 1256558401 is about 1079.0980126116.

The spelling of 1256558401 in words is "one billion, two hundred fifty-six million, five hundred fifty-eight thousand, four hundred one".