256394391782400 has 297 divisors, whose sum is σ = 918040740306781. Its totient is φ = 68369788231680.

The previous prime is 256394391782371. The next prime is 256394391782401. The reversal of 256394391782400 is 4287193493652.

The square root of 256394391782400 is 16012320.

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

256394391782400 is a `hidden beast` number, since 2 + 5 + 6 + 3 + 9 + 439 + 178 + 24 + 0 + 0 = 666.

It can be written as a sum of positive squares in only one way, i.e., 92301981041664 + 164092410740736 = 9607392^2 + 12809856^2 .

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (256394391782401) by changing a digit.

It is a polite number, since it can be written in 26 ways as a sum of consecutive naturals, for example, 7685896921 + ... + 7685930279.

It is a 1-persistent number, because it is pandigital, but 2⋅256394391782400 = 512788783564800 is not.

Almost surely, 2^{256394391782400} is an apocalyptic number.

256394391782400 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

256394391782400 is the 16012320-th square number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256394391782400

256394391782400 is an abundant number, since it is smaller than the sum of its proper divisors (661646348524381).

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

256394391782400 is an frugal number, since it uses more digits than its factorization.

256394391782400 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 66754 (or 33369 counting only the distinct ones).

The product of its (nonzero) digits is 78382080, while the sum is 63.

The spelling of 256394391782400 in words is "two hundred fifty-six trillion, three hundred ninety-four billion, three hundred ninety-one million, seven hundred eighty-two thousand, four hundred".