998975489 has 2 divisors, whose sum is σ = 998975490. Its totient is φ = 998975488.

The previous prime is 998975479. The next prime is 998975531. The reversal of 998975489 is 984579899.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 807014464 + 191961025 = 28408^2 + 13855^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-998975489 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is not a weakly prime, because it can be changed into another prime (998975449) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499487744 + 499487745.

It is an arithmetic number, because the mean of its divisors is an integer number (499487745).

Almost surely, 2^998975489 is an apocalyptic number.

It is an amenable number.

998975489 is a deficient number, since it is larger than the sum of its proper divisors (1).

998975489 is an equidigital number, since it uses as much as digits as its factorization.

998975489 is an evil number, because the sum of its binary digits is even.

The product of its digits is 58786560, while the sum is 68.

The square root of 998975489 is about 31606.5735093192. The cubic root of 998975489 is about 999.6583796422.

The spelling of 998975489 in words is "nine hundred ninety-eight million, nine hundred seventy-five thousand, four hundred eighty-nine".