998005 has 4 divisors (see below), whose sum is σ = 1197612. Its totient is φ = 798400.

The previous prime is 997991. The next prime is 998009. The reversal of 998005 is 500899.

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

It can be written as a sum of positive squares in 2 ways, for example, as 361201 + 636804 = 601^2 + 798^2 .

It is not a de Polignac number, because 998005 - 2⁵ = 997973 is a prime.

It is a Smith number, since the sum of its digits (31) coincides with the sum of the digits of its prime factors. Since it is squarefree, it is also a hoax number.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (998009) 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 in 3 ways as a sum of consecutive naturals, for example, 99796 + ... + 99805.

It is an arithmetic number, because the mean of its divisors is an integer number (299403).

2⁹⁹⁸⁰⁰⁵ is an apocalyptic number.

It is an amenable number.

998005 is a deficient number, since it is larger than the sum of its proper divisors (199607).

998005 is a wasteful number, since it uses less digits than its factorization.

998005 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 199606.

The product of its (nonzero) digits is 3240, while the sum is 31.

The square root of 998005 is about 999.0020020000. The cubic root of 998005 is about 99.9334557284.

The spelling of 998005 in words is "nine hundred ninety-eight thousand, five".