19505391688 has 16 divisors (see below), whose sum is σ = 36583839360. Its totient is φ = 9749701200.

The previous prime is 19505391679. The next prime is 19505391691. The reversal of 19505391688 is 88619350591.

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 3 ways as a sum of consecutive naturals, for example, 346528 + ... + 398863.

It is an arithmetic number, because the mean of its divisors is an integer number (2286489960).

Almost surely, 2^19505391688 is an apocalyptic number.

It is an amenable number.

19505391688 is a deficient number, since it is larger than the sum of its proper divisors (17078447672).

19505391688 is a wasteful number, since it uses less digits than its factorization.

19505391688 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 748668 (or 748664 counting only the distinct ones).

The product of its (nonzero) digits is 2332800, while the sum is 55.

The spelling of 19505391688 in words is "nineteen billion, five hundred five million, three hundred ninety-one thousand, six hundred eighty-eight".