256042393421 has 8 divisors (see below), whose sum is σ = 265229882400. Its totient is φ = 246878800560.

The previous prime is 256042393357. The next prime is 256042393423. The reversal of 256042393421 is 124393240652.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 256042393421 - 2⁶ = 256042393357 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256042393423) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 5952215 + ... + 5995076.

It is an arithmetic number, because the mean of its divisors is an integer number (33153735300).

Almost surely, 2^256042393421 is an apocalyptic number.

It is an amenable number.

256042393421 is a deficient number, since it is larger than the sum of its proper divisors (9187488979).

256042393421 is a wasteful number, since it uses less digits than its factorization.

256042393421 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 11948059.

The product of its (nonzero) digits is 311040, while the sum is 41.

The spelling of 256042393421 in words is "two hundred fifty-six billion, forty-two million, three hundred ninety-three thousand, four hundred twenty-one".