19112991897 has 16 divisors (see below), whose sum is σ = 27148599360. Its totient is φ = 11918886912.

The previous prime is 19112991823. The next prime is 19112991949. The reversal of 19112991897 is 79819921191.

It is not a de Polignac number, because 19112991897 - 2¹⁰ = 19112990873 is a prime.

It is not an unprimeable number, because it can be changed into a prime (19112991817) 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 15 ways as a sum of consecutive naturals, for example, 1141272 + ... + 1157897.

It is an arithmetic number, because the mean of its divisors is an integer number (1696787460).

Almost surely, 2^19112991897 is an apocalyptic number.

19112991897 is a gapful number since it is divisible by the number (17) formed by its first and last digit.

It is an amenable number.

19112991897 is a deficient number, since it is larger than the sum of its proper divisors (8035607463).

19112991897 is a wasteful number, since it uses less digits than its factorization.

19112991897 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2299352.

The product of its digits is 734832, while the sum is 57.

The spelling of 19112991897 in words is "nineteen billion, one hundred twelve million, nine hundred ninety-one thousand, eight hundred ninety-seven".