990398 has 4 divisors (see below), whose sum is σ = 1485600. Its totient is φ = 495198.

The previous prime is 990397. The next prime is 990463. The reversal of 990398 is 893099.

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

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (990397) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 247598 + ... + 247601.

It is an arithmetic number, because the mean of its divisors is an integer number (371400).

2⁹⁹⁰³⁹⁸ is an apocalyptic number.

990398 is a deficient number, since it is larger than the sum of its proper divisors (495202).

990398 is a wasteful number, since it uses less digits than its factorization.

990398 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 495201.

The product of its (nonzero) digits is 17496, while the sum is 38.

The square root of 990398 is about 995.1874195346. The cubic root of 990398 is about 99.6789034066.

It can be divided in two parts, 9903 and 98, that added together give a palindrome (10001).

The spelling of 990398 in words is "nine hundred ninety thousand, three hundred ninety-eight".