8191873329889 has 4 divisors (see below), whose sum is σ = 8212507771924. Its totient is φ = 8171238887856.

The previous prime is 8191873329883. The next prime is 8191873329947. The reversal of 8191873329889 is 9889233781918.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 3569201328289 + 4622672001600 = 1889233^2 + 2150040^2 .

It is a cyclic number.

It is not a de Polignac number, because 8191873329889 - 2¹⁵ = 8191873297121 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (8191873329883) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 10317220422 + ... + 10317221215.

It is an arithmetic number, because the mean of its divisors is an integer number (2053126942981).

Almost surely, 2^{8191873329889} is an apocalyptic number.

It is an amenable number.

8191873329889 is a deficient number, since it is larger than the sum of its proper divisors (20634442035).

8191873329889 is a wasteful number, since it uses less digits than its factorization.

8191873329889 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20634442034.

The product of its digits is 376233984, while the sum is 76.

The spelling of 8191873329889 in words is "eight trillion, one hundred ninety-one billion, eight hundred seventy-three million, three hundred twenty-nine thousand, eight hundred eighty-nine".