999899998 has 16 divisors (see below), whose sum is σ = 1525248000. Its totient is φ = 491537592.

The previous prime is 999899987. The next prime is 999900017. The reversal of 999899998 is 899998999.

It is a Harshad number since it is a multiple of its sum of digits (79).

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24523 + ... + 51001.

It is an arithmetic number, because the mean of its divisors is an integer number (95328000).

Almost surely, 2^999899998 is an apocalyptic number.

999899998 is a deficient number, since it is larger than the sum of its proper divisors (525348002).

999899998 is a wasteful number, since it uses less digits than its factorization.

999899998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 26799.

The product of its digits is 306110016, while the sum is 79.

The square root of 999899998 is about 31621.1953916989. The cubic root of 999899998 is about 999.9666648888.

Subtracting from 999899998 its reverse (899998999), we obtain a palindrome (99900999).

The spelling of 999899998 in words is "nine hundred ninety-nine million, eight hundred ninety-nine thousand, nine hundred ninety-eight".