998123321899 has 4 divisors (see below), whose sum is σ = 1088861805720. Its totient is φ = 907384838080.

The previous prime is 998123321879. The next prime is 998123321927.

998123321899 is nontrivially palindromic in base 10.

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

It is a cyclic number.

It is not a de Polignac number, because 998123321899 - 2⁹ = 998123321387 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 998123321899.

It is not an unprimeable number, because it can be changed into a prime (998123321879) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 45369241894 + ... + 45369241915.

It is an arithmetic number, because the mean of its divisors is an integer number (272215451430).

Almost surely, 2^998123321899 is an apocalyptic number.

998123321899 is a deficient number, since it is larger than the sum of its proper divisors (90738483821).

998123321899 is a wasteful number, since it uses less digits than its factorization.

998123321899 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 90738483820.

The product of its digits is 15116544, while the sum is 64.

The spelling of 998123321899 in words is "nine hundred ninety-eight billion, one hundred twenty-three million, three hundred twenty-one thousand, eight hundred ninety-nine".