998999799897 has 16 divisors (see below), whose sum is σ = 1454847720192. Its totient is φ = 604722298320.

The previous prime is 998999799881. The next prime is 998999799913. The reversal of 998999799897 is 798997999899.

It is a happy number.

It is an interprime number because it is at equal distance from previous prime (998999799881) and next prime (998999799913).

It is not a de Polignac number, because 998999799897 - 2⁴ = 998999799881 is a prime.

It is not an unprimeable number, because it can be changed into a prime (998999799397) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 18275443 + ... + 18330024.

It is an arithmetic number, because the mean of its divisors is an integer number (90927982512).

Almost surely, 2^998999799897 is an apocalyptic number.

It is an amenable number.

998999799897 is a deficient number, since it is larger than the sum of its proper divisors (455847920295).

998999799897 is a wasteful number, since it uses less digits than its factorization.

998999799897 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 36606308.

The product of its digits is 134994517056, while the sum is 102.

The spelling of 998999799897 in words is "nine hundred ninety-eight billion, nine hundred ninety-nine million, seven hundred ninety-nine thousand, eight hundred ninety-seven".