19641056256 has 308 divisors, whose sum is σ = 59764654152. Its totient is φ = 6447734784.

The previous prime is 19641056243. The next prime is 19641056261. The reversal of 19641056256 is 65265014691.

19641056256 is a `hidden beast` number, since 1 + 9 + 6 + 4 + 10 + 5 + 625 + 6 = 666.

It is a congruent number.

It is an unprimeable number.

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 27 ways as a sum of consecutive naturals, for example, 61959010 + ... + 61959326.

Almost surely, 2^19641056256 is an apocalyptic number.

19641056256 is a gapful number since it is divisible by the number (16) 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 19641056256, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29882327076).

19641056256 is an abundant number, since it is smaller than the sum of its proper divisors (40123597896).

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

19641056256 is an frugal number, since it uses more digits than its factorization.

19641056256 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 438 (or 405 counting only the distinct ones).

The product of its (nonzero) digits is 388800, while the sum is 45.

The spelling of 19641056256 in words is "nineteen billion, six hundred forty-one million, fifty-six thousand, two hundred fifty-six".