256500420242125 has 8 divisors (see below), whose sum is σ = 320112524462328. Its totient is φ = 205200336193600.

The previous prime is 256500420242117. The next prime is 256500420242201. The reversal of 256500420242125 is 521242024005652.

It can be written as a sum of positive squares in 4 ways, for example, as 17347000090729 + 239153420151396 = 4164973^2 + 15464586^2 .

It is not a de Polignac number, because 256500420242125 - 2³ = 256500420242117 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1026001680844 + ... + 1026001681093.

It is an arithmetic number, because the mean of its divisors is an integer number (40014065557791).

Almost surely, 2^{256500420242125} is an apocalyptic number.

256500420242125 is a gapful number since it is divisible by the number (25) formed by its first and last digit.

It is an amenable number.

256500420242125 is a deficient number, since it is larger than the sum of its proper divisors (63612104220203).

256500420242125 is an equidigital number, since it uses as much as digits as its factorization.

256500420242125 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2052003361952 (or 2052003361942 counting only the distinct ones).

The product of its (nonzero) digits is 384000, while the sum is 40.

Adding to 256500420242125 its reverse (521242024005652), we get a palindrome (777742444247777).

The spelling of 256500420242125 in words is "two hundred fifty-six trillion, five hundred billion, four hundred twenty million, two hundred forty-two thousand, one hundred twenty-five".