256396398736 has 45 divisors (see below), whose sum is σ = 499661228619. Its totient is φ = 127455881472.

The previous prime is 256396398679. The next prime is 256396398743. The reversal of 256396398736 is 637893693652.

The square root of 256396398736 is 506356.

It is a perfect power (a square), and thus also a powerful number.

It can be written as a sum of positive squares in 4 ways, for example, as 684136336 + 255712262400 = 26156^2 + 505680^2 .

It is a super-2 number, since 2×256396398736² (a number of 24 digits) contains 22 as substring.

It is a Duffinian number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 8 ways as a sum of consecutive naturals, for example, 561042220 + ... + 561042676.

Almost surely, 2^256396398736 is an apocalyptic number.

256396398736 is the 506356-th square number.

It is an amenable number.

256396398736 is a deficient number, since it is larger than the sum of its proper divisors (243264829883).

256396398736 is an frugal number, since it uses more digits than its factorization.

256396398736 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1476 (or 736 counting only the distinct ones).

The product of its digits is 264539520, while the sum is 67.

The spelling of 256396398736 in words is "two hundred fifty-six billion, three hundred ninety-six million, three hundred ninety-eight thousand, seven hundred thirty-six".