256564426071646 has 128 divisors (see below), whose sum is σ = 510019890315264. Its totient is φ = 93712886392320.

The previous prime is 256564426071623. The next prime is 256564426071647. The reversal of 256564426071646 is 646170624465652.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256564426071647) by changing a digit.

It is a polite number, since it can be written in 63 ways as a sum of consecutive naturals, for example, 703800595 + ... + 704165041.

It is an arithmetic number, because the mean of its divisors is an integer number (3984530393088).

Almost surely, 2^{256564426071646} is an apocalyptic number.

256564426071646 is a deficient number, since it is larger than the sum of its proper divisors (253455464243618).

256564426071646 is a wasteful number, since it uses less digits than its factorization.

256564426071646 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 365534.

The product of its (nonzero) digits is 348364800, while the sum is 64.

The spelling of 256564426071646 in words is "two hundred fifty-six trillion, five hundred sixty-four billion, four hundred twenty-six million, seventy-one thousand, six hundred forty-six".