19439139819 has 32 divisors (see below), whose sum is σ = 29173478400. Its totient is φ = 11412610560.

The previous prime is 19439139773. The next prime is 19439139823. The reversal of 19439139819 is 91893193491.

It is not a de Polignac number, because 19439139819 - 2⁷ = 19439139691 is a prime.

It is a super-2 number, since 2×19439139819² (a number of 21 digits) contains 22 as substring.

It is a Smith number, since the sum of its digits (57) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is not an unprimeable number, because it can be changed into a prime (19439139859) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 67827 + ... + 208515.

It is an arithmetic number, because the mean of its divisors is an integer number (911671200).

Almost surely, 2^19439139819 is an apocalyptic number.

19439139819 is a deficient number, since it is larger than the sum of its proper divisors (9734338581).

19439139819 is a wasteful number, since it uses less digits than its factorization.

19439139819 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 140835.

The product of its digits is 1889568, while the sum is 57.

The spelling of 19439139819 in words is "nineteen billion, four hundred thirty-nine million, one hundred thirty-nine thousand, eight hundred nineteen".