1999999998 has 40 divisors (see below), whose sum is σ = 4602616392. Its totient is φ = 648646704.

The previous prime is 1999999973. The next prime is 2000000011. The reversal of 1999999998 is 8999999991.

It is a Harshad number since it is a multiple of its sum of digits (81).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 19 ways as a sum of consecutive naturals, for example, 160840 + ... + 172827.

Almost surely, 2^1999999998 is an apocalyptic number.

1999999998 is a gapful number since it is divisible by the number (18) formed by its first and last digit.

1999999998 is an abundant number, since it is smaller than the sum of its proper divisors (2602616394).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

1999999998 is a wasteful number, since it uses less digits than its factorization.

1999999998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333718 (or 333709 counting only the distinct ones).

The product of its digits is 344373768, while the sum is 81.

The square root of 1999999998 is about 44721.3595276351. The cubic root of 1999999998 is about 1259.9210494749.

It can be divided in two parts, 1 and 999999998, that added together give a palindrome (999999999).

The spelling of 1999999998 in words is "one billion, nine hundred ninety-nine million, nine hundred ninety-nine thousand, nine hundred ninety-eight".