998999799999 has 24 divisors (see below), whose sum is σ = 1394013185712. Its totient is φ = 636319368960.

The previous prime is 998999799929. The next prime is 998999800009. The reversal of 998999799999 is 999997999899.

It is a happy number.

It is not a de Polignac number, because 998999799999 - 2¹⁶ = 998999734463 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 998999799897 and 998999799906.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (998999799929) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 1040889 + ... + 1755405.

It is an arithmetic number, because the mean of its divisors is an integer number (58083882738).

Almost surely, 2^998999799999 is an apocalyptic number.

998999799999 is a deficient number, since it is larger than the sum of its proper divisors (395013385713).

998999799999 is a wasteful number, since it uses less digits than its factorization.

998999799999 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 715447 (or 715424 counting only the distinct ones).

The product of its digits is 195259926456, while the sum is 105.

The spelling of 998999799999 in words is "nine hundred ninety-eight billion, nine hundred ninety-nine million, seven hundred ninety-nine thousand, nine hundred ninety-nine".