19904798090 has 16 divisors (see below), whose sum is σ = 35930140488. Its totient is φ = 7939362816.

The previous prime is 19904798071. The next prime is 19904798093. The reversal of 19904798090 is 9089740991.

It can be written as a sum of positive squares in 4 ways, for example, as 19174771729 + 730026361 = 138473^2 + 27019^2 .

It is not an unprimeable number, because it can be changed into a prime (19904798093) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 2815847 + ... + 2822906.

Almost surely, 2^19904798090 is an apocalyptic number.

19904798090 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

19904798090 is a deficient number, since it is larger than the sum of its proper divisors (16025342398).

19904798090 is a wasteful number, since it uses less digits than its factorization.

19904798090 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 5639113.

The product of its (nonzero) digits is 1469664, while the sum is 56.

The spelling of 19904798090 in words is "nineteen billion, nine hundred four million, seven hundred ninety-eight thousand, ninety".