19919019100 has 36 divisors (see below), whose sum is σ = 43539807024. Its totient is φ = 7909444480.

The previous prime is 19919019077. The next prime is 19919019101. The reversal of 19919019100 is 191091991.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (19919019101) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 713272 + ... + 740671.

It is an arithmetic number, because the mean of its divisors is an integer number (1209439084).

Almost surely, 2^19919019100 is an apocalyptic number.

19919019100 is a gapful number since it is divisible by the number (10) formed by its first and last digit.

It is an amenable number.

19919019100 is an abundant number, since it is smaller than the sum of its proper divisors (23620787924).

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

19919019100 is a wasteful number, since it uses less digits than its factorization.

19919019100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1454094 (or 1454087 counting only the distinct ones).

The product of its (nonzero) digits is 6561, while the sum is 40.

The spelling of 19919019100 in words is "nineteen billion, nine hundred nineteen million, nineteen thousand, one hundred".