998810689 has 2 divisors, whose sum is σ = 998810690. Its totient is φ = 998810688.

The previous prime is 998810641. The next prime is 998810723. The reversal of 998810689 is 986018899.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 928116225 + 70694464 = 30465^2 + 8408^2 .

It is a cyclic number.

It is not a de Polignac number, because 998810689 - 2⁹ = 998810177 is a prime.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (998810789) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499405344 + 499405345.

It is an arithmetic number, because the mean of its divisors is an integer number (499405345).

Almost surely, 2^998810689 is an apocalyptic number.

It is an amenable number.

998810689 is a deficient number, since it is larger than the sum of its proper divisors (1).

998810689 is an equidigital number, since it uses as much as digits as its factorization.

998810689 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2239488, while the sum is 58.

The square root of 998810689 is about 31603.9663491784. The cubic root of 998810689 is about 999.6034057338.

The spelling of 998810689 in words is "nine hundred ninety-eight million, eight hundred ten thousand, six hundred eighty-nine".