1998499999 has 2 divisors, whose sum is σ = 1998500000. Its totient is φ = 1998499998.

The previous prime is 1998499963. The next prime is 1998500003. The reversal of 1998499999 is 9999948991.

It is a strong prime.

It is an emirp because it is prime and its reverse (9999948991) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1998499999 - 2¹⁵ = 1998467231 is a prime.

1998499999 is a modest number, since divided by 99999 gives 19984 as remainder.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1998499099) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 999249999 + 999250000.

It is an arithmetic number, because the mean of its divisors is an integer number (999250000).

Almost surely, 2^1998499999 is an apocalyptic number.

1998499999 is a deficient number, since it is larger than the sum of its proper divisors (1).

1998499999 is an equidigital number, since it uses as much as digits as its factorization.

1998499999 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 153055008, while the sum is 76.

The square root of 1998499999 is about 44704.5858833297. The cubic root of 1998499999 is about 1259.6059906444.

The spelling of 1998499999 in words is "one billion, nine hundred ninety-eight million, four hundred ninety-nine thousand, nine hundred ninety-nine".