998817718099 has 2 divisors, whose sum is σ = 998817718100. Its totient is φ = 998817718098.

The previous prime is 998817718051. The next prime is 998817718127. The reversal of 998817718099 is 990817718899.

It is a strong prime.

It is an emirp because it is prime and its reverse (990817718899) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 998817718099 - 2²⁷ = 998683500371 is a prime.

It is not a weakly prime, because it can be changed into another prime (998817712099) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499408859049 + 499408859050.

It is an arithmetic number, because the mean of its divisors is an integer number (499408859050).

Almost surely, 2^998817718099 is an apocalyptic number.

998817718099 is a deficient number, since it is larger than the sum of its proper divisors (1).

998817718099 is an equidigital number, since it uses as much as digits as its factorization.

998817718099 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 164602368, while the sum is 76.

The spelling of 998817718099 in words is "nine hundred ninety-eight billion, eight hundred seventeen million, seven hundred eighteen thousand, ninety-nine".