256839839401 has 4 divisors (see below), whose sum is σ = 256845060100. Its totient is φ = 256834618704.

The previous prime is 256839839381. The next prime is 256839839419. The reversal of 256839839401 is 104938938652.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 135791513001 + 121048326400 = 368499^2 + 347920^2 .

It is a cyclic number.

It is not a de Polignac number, because 256839839401 - 2²⁹ = 256302968489 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256839839801) 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 3 ways as a sum of consecutive naturals, for example, 2535846 + ... + 2635183.

It is an arithmetic number, because the mean of its divisors is an integer number (64211265025).

Almost surely, 2^256839839401 is an apocalyptic number.

It is an amenable number.

256839839401 is a deficient number, since it is larger than the sum of its proper divisors (5220699).

256839839401 is an equidigital number, since it uses as much as digits as its factorization.

256839839401 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5220698.

The product of its (nonzero) digits is 11197440, while the sum is 58.

The spelling of 256839839401 in words is "two hundred fifty-six billion, eight hundred thirty-nine million, eight hundred thirty-nine thousand, four hundred one".