999205 has 8 divisors (see below), whose sum is σ = 1204632. Its totient is φ = 795648.

The previous prime is 999199. The next prime is 999217. The reversal of 999205 is 502999.

It can be written as a sum of positive squares in 4 ways, for example, as 66049 + 933156 = 257^2 + 966^2 .

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 999205 - 2¹⁹ = 474917 is a prime.

It is a Duffinian number.

999205 is a lucky number.

It is a congruent number.

It is an unprimeable number.

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 7 ways as a sum of consecutive naturals, for example, 1389 + ... + 1981.

It is an arithmetic number, because the mean of its divisors is an integer number (150579).

2⁹⁹⁹²⁰⁵ is an apocalyptic number.

It is an amenable number.

999205 is a deficient number, since it is larger than the sum of its proper divisors (205427).

999205 is a wasteful number, since it uses less digits than its factorization.

999205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 935.

The product of its (nonzero) digits is 7290, while the sum is 34.

The square root of 999205 is about 999.6024209655. The cubic root of 999205 is about 99.9734929744.

The spelling of 999205 in words is "nine hundred ninety-nine thousand, two hundred five".