999797998 has 4 divisors (see below), whose sum is σ = 1499697000. Its totient is φ = 499898998.

The previous prime is 999797987. The next prime is 999798001. The reversal of 999797998 is 899797999.

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 an unprimeable number.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 249949498 + ... + 249949501.

It is an arithmetic number, because the mean of its divisors is an integer number (374924250).

Almost surely, 2^999797998 is an apocalyptic number.

999797998 is a deficient number, since it is larger than the sum of its proper divisors (499899002).

999797998 is a wasteful number, since it uses less digits than its factorization.

999797998 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 499899001.

The product of its digits is 208324872, while the sum is 76.

The square root of 999797998 is about 31619.5825083128. The cubic root of 999797998 is about 999.9326614656.

Subtracting from 999797998 its reverse (899797999), we obtain a palindrome (99999999).

The spelling of 999797998 in words is "nine hundred ninety-nine million, seven hundred ninety-seven thousand, nine hundred ninety-eight".