999959998 has 4 divisors (see below), whose sum is σ = 1499940000. Its totient is φ = 499979998.

The previous prime is 999959993. The next prime is 999960011. The reversal of 999959998 is 899959999.

It is a happy number.

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

It is a Smith number, since the sum of its digits (76) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (999959993) 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, 249989998 + ... + 249990001.

It is an arithmetic number, because the mean of its divisors is an integer number (374985000).

Almost surely, 2^999959998 is an apocalyptic number.

999959998 is a deficient number, since it is larger than the sum of its proper divisors (499980002).

999959998 is a wasteful number, since it uses less digits than its factorization.

999959998 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 499980001.

The product of its digits is 191318760, while the sum is 76.

The square root of 999959998 is about 31622.1441082037. The cubic root of 999959998 is about 999.9866658222.

Subtracting from 999959998 its reverse (899959999), we obtain a palindrome (99999999).

The spelling of 999959998 in words is "nine hundred ninety-nine million, nine hundred fifty-nine thousand, nine hundred ninety-eight".