19642581864 has 64 divisors (see below), whose sum is σ = 57772310400. Its totient is φ = 6162377472.

The previous prime is 19642581851. The next prime is 19642581899. The reversal of 19642581864 is 46818524691.

19642581864 is a `hidden beast` number, since 19 + 6 + 42 + 581 + 8 + 6 + 4 = 666.

It is a Harshad number since it is a multiple of its sum of digits (54).

It is a self number, because there is not a number n which added to its sum of digits gives 19642581864.

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 15 ways as a sum of consecutive naturals, for example, 2670972 + ... + 2678315.

It is an arithmetic number, because the mean of its divisors is an integer number (902692350).

Almost surely, 2^19642581864 is an apocalyptic number.

It is an amenable number.

19642581864 is an abundant number, since it is smaller than the sum of its proper divisors (38129728536).

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

19642581864 is a wasteful number, since it uses less digits than its factorization.

19642581864 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5349319 (or 5349309 counting only the distinct ones).

The product of its digits is 3317760, while the sum is 54.

The spelling of 19642581864 in words is "nineteen billion, six hundred forty-two million, five hundred eighty-one thousand, eight hundred sixty-four".