256419873438 has 48 divisors (see below), whose sum is σ = 521343682560. Its totient is φ = 84078297792.

The previous prime is 256419873403. The next prime is 256419873467. The reversal of 256419873438 is 834378914652.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 12235573 + ... + 12256511.

It is an arithmetic number, because the mean of its divisors is an integer number (10861326720).

Almost surely, 2^256419873438 is an apocalyptic number.

256419873438 is an abundant number, since it is smaller than the sum of its proper divisors (264923809122).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

256419873438 is a wasteful number, since it uses less digits than its factorization.

256419873438 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21473 (or 21400 counting only the distinct ones).

The product of its digits is 34836480, while the sum is 60.

The spelling of 256419873438 in words is "two hundred fifty-six billion, four hundred nineteen million, eight hundred seventy-three thousand, four hundred thirty-eight".