256605215644 has 12 divisors (see below), whose sum is σ = 449064510664. Its totient is φ = 128301069744.

The previous prime is 256605215641. The next prime is 256605215681. The reversal of 256605215644 is 446512506652.

It is a junction number, because it is equal to n+sod(n) for n = 256605215594 and 256605215603.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256605215641) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 43894 + ... + 717730.

Almost surely, 2^256605215644 is an apocalyptic number.

It is an amenable number.

256605215644 is a deficient number, since it is larger than the sum of its proper divisors (192459295020).

256605215644 is a wasteful number, since it uses less digits than its factorization.

256605215644 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 769044 (or 769042 counting only the distinct ones).

The product of its (nonzero) digits is 1728000, while the sum is 46.

The spelling of 256605215644 in words is "two hundred fifty-six billion, six hundred five million, two hundred fifteen thousand, six hundred forty-four".