256399824 has 40 divisors (see below), whose sum is σ = 663073632. Its totient is φ = 85375360.

The previous prime is 256399823. The next prime is 256399861. The reversal of 256399824 is 428993652.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (48).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (256399823) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 54427 + ... + 58949.

Almost surely, 2^256399824 is an apocalyptic number.

256399824 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

256399824 is an abundant number, since it is smaller than the sum of its proper divisors (406673808).

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

256399824 is a wasteful number, since it uses less digits than its factorization.

256399824 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5715 (or 5709 counting only the distinct ones).

The product of its digits is 933120, while the sum is 48.

The square root of 256399824 is about 16012.4896252894. The cubic root of 256399824 is about 635.2908118847.

The spelling of 256399824 in words is "two hundred fifty-six million, three hundred ninety-nine thousand, eight hundred twenty-four".