998646889 has 2 divisors, whose sum is σ = 998646890. Its totient is φ = 998646888.

The previous prime is 998646877. The next prime is 998646917. The reversal of 998646889 is 988646899.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 644906025 + 353740864 = 25395^2 + 18808^2 .

It is a cyclic number.

It is not a de Polignac number, because 998646889 - 2²¹ = 996549737 is a prime.

It is not a weakly prime, because it can be changed into another prime (998646809) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 499323444 + 499323445.

It is an arithmetic number, because the mean of its divisors is an integer number (499323445).

Almost surely, 2^998646889 is an apocalyptic number.

It is an amenable number.

998646889 is a deficient number, since it is larger than the sum of its proper divisors (1).

998646889 is an equidigital number, since it uses as much as digits as its factorization.

998646889 is an evil number, because the sum of its binary digits is even.

The product of its digits is 53747712, while the sum is 67.

The square root of 998646889 is about 31601.3747960433. The cubic root of 998646889 is about 999.5487594126.

The spelling of 998646889 in words is "nine hundred ninety-eight million, six hundred forty-six thousand, eight hundred eighty-nine".