19989789090 has 32 divisors (see below), whose sum is σ = 49272131520. Its totient is φ = 5186539584.

The previous prime is 19989789077. The next prime is 19989789091. The reversal of 19989789090 is 9098798991.

It is not an unprimeable number, because it can be changed into a prime (19989789091) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 9003300 + ... + 9005519.

It is an arithmetic number, because the mean of its divisors is an integer number (1539754110).

Almost surely, 2^19989789090 is an apocalyptic number.

19989789090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19989789090 is an abundant number, since it is smaller than the sum of its proper divisors (29282342430).

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

19989789090 is a wasteful number, since it uses less digits than its factorization.

19989789090 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18008866.

The product of its (nonzero) digits is 26453952, while the sum is 69.

The spelling of 19989789090 in words is "nineteen billion, nine hundred eighty-nine million, seven hundred eighty-nine thousand, ninety".