990205 has 8 divisors (see below), whose sum is σ = 1229400. Its totient is φ = 764736.

The previous prime is 990181. The next prime is 990211. The reversal of 990205 is 502099.

It can be written as a sum of positive squares in 4 ways, for example, as 119716 + 870489 = 346^2 + 933^2 .

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 990205 - 2¹¹ = 988157 is a prime.

990205 is a lucky number.

It is a self number, because there is not a number n which added to its sum of digits gives 990205.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 3270 + ... + 3559.

It is an arithmetic number, because the mean of its divisors is an integer number (153675).

2⁹⁹⁰²⁰⁵ is an apocalyptic number.

It is an amenable number.

990205 is a deficient number, since it is larger than the sum of its proper divisors (239195).

990205 is a wasteful number, since it uses less digits than its factorization.

990205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 6863.

The product of its (nonzero) digits is 810, while the sum is 25.

The square root of 990205 is about 995.0904481503. The cubic root of 990205 is about 99.6724281384.

The spelling of 990205 in words is "nine hundred ninety thousand, two hundred five".