19919642388 has 24 divisors (see below), whose sum is σ = 47067511680. Its totient is φ = 6555831360.

The previous prime is 19919642383. The next prime is 19919642399. The reversal of 19919642388 is 88324691991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19919642383) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 10505193 + ... + 10507088.

It is an arithmetic number, because the mean of its divisors is an integer number (1961146320).

Almost surely, 2^19919642388 is an apocalyptic number.

It is an amenable number.

19919642388 is an abundant number, since it is smaller than the sum of its proper divisors (27147869292).

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

19919642388 is a wasteful number, since it uses less digits than its factorization.

19919642388 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 21012367 (or 21012365 counting only the distinct ones).

The product of its digits is 6718464, while the sum is 60.

The spelling of 19919642388 in words is "nineteen billion, nine hundred nineteen million, six hundred forty-two thousand, three hundred eighty-eight".