256805506385064 has 384 divisors, whose sum is σ = 873765337536000. Its totient is φ = 67707429672960.

The previous prime is 256805506385059. The next prime is 256805506385111. The reversal of 256805506385064 is 460583605508652.

It is a happy number.

256805506385064 is a `hidden beast` number, since 2 + 5 + 68 + 0 + 5 + 5 + 0 + 63 + 8 + 506 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (63).

It is a junction number, because it is equal to n+sod(n) for n = 256805506384992 and 256805506385010.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 1024338832 + ... + 1024589504.

It is an arithmetic number, because the mean of its divisors is an integer number (2275430566500).

Almost surely, 2^{256805506385064} is an apocalyptic number.

256805506385064 is a gapful number since it is divisible by the number (24) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 256805506385064, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (436882668768000).

256805506385064 is an abundant number, since it is smaller than the sum of its proper divisors (616959831150936).

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

256805506385064 is a wasteful number, since it uses less digits than its factorization.

256805506385064 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 253910 (or 253889 counting only the distinct ones).

The product of its (nonzero) digits is 207360000, while the sum is 63.

The spelling of 256805506385064 in words is "two hundred fifty-six trillion, eight hundred five billion, five hundred six million, three hundred eighty-five thousand, sixty-four".