999998998 has 4 divisors (see below), whose sum is σ = 1499998500. Its totient is φ = 499999498.

The previous prime is 999998981. The next prime is 999999001. The reversal of 999998998 is 899899999.

It is a semiprime because it is the product of two primes.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 249999748 + ... + 249999751.

It is an arithmetic number, because the mean of its divisors is an integer number (374999625).

Almost surely, 2^999998998 is an apocalyptic number.

999998998 is a deficient number, since it is larger than the sum of its proper divisors (499999502).

999998998 is a wasteful number, since it uses less digits than its factorization.

999998998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 499999501.

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

The square root of 999998998 is about 31622.7607586687. The cubic root of 999998998 is about 999.9996659999. Note that the first 3 decimals are identical.

The spelling of 999998998 in words is "nine hundred ninety-nine million, nine hundred ninety-eight thousand, nine hundred ninety-eight".