19928991090 has 128 divisors (see below), whose sum is σ = 49517568000. Its totient is φ = 5130867456.

The previous prime is 19928991067. The next prime is 19928991101. The reversal of 19928991090 is 9019982991.

It is a self number, because there is not a number n which added to its sum of digits gives 19928991090.

It is an unprimeable number.

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 63 ways as a sum of consecutive naturals, for example, 50198772 + ... + 50199168.

It is an arithmetic number, because the mean of its divisors is an integer number (386856000).

Almost surely, 2^19928991090 is an apocalyptic number.

19928991090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is a practical number, because each smaller number is the sum of distinct divisors of 19928991090, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24758784000).

19928991090 is an abundant number, since it is smaller than the sum of its proper divisors (29588576910).

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

19928991090 is a wasteful number, since it uses less digits than its factorization.

19928991090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 904.

The product of its (nonzero) digits is 944784, while the sum is 57.

The spelling of 19928991090 in words is "nineteen billion, nine hundred twenty-eight million, nine hundred ninety-one thousand, ninety".