998817718899 has 128 divisors (see below), whose sum is σ = 1810448640000. Its totient is φ = 472994795520.

The previous prime is 998817718867. The next prime is 998817718909.

It is a happy number.

998817718899 is nontrivially palindromic in base 10.

998817718899 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 998817718899 - 2⁵ = 998817718867 is a prime.

It is not an unprimeable number, because it can be changed into a prime (998817718099) by changing a digit.

It is a polite number, since it can be written in 127 ways as a sum of consecutive naturals, for example, 102448477 + ... + 102458225.

It is an arithmetic number, because the mean of its divisors is an integer number (14144130000).

Almost surely, 2^998817718899 is an apocalyptic number.

998817718899 is a deficient number, since it is larger than the sum of its proper divisors (811630921101).

998817718899 is a wasteful number, since it uses less digits than its factorization.

998817718899 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10205.

The product of its digits is 1316818944, while the sum is 84.

The spelling of 998817718899 in words is "nine hundred ninety-eight billion, eight hundred seventeen million, seven hundred eighteen thousand, eight hundred ninety-nine".