205867990 has 16 divisors (see below), whose sum is σ = 378447552. Its totient is φ = 80594944.

The previous prime is 205867969. The next prime is 205867999. The reversal of 205867990 is 99768502.

205867990 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a self number, because there is not a number n which added to its sum of digits gives 205867990.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (205867999) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 218539 + ... + 219478.

It is an arithmetic number, because the mean of its divisors is an integer number (23652972).

Almost surely, 2^205867990 is an apocalyptic number.

205867990 is a deficient number, since it is larger than the sum of its proper divisors (172579562).

205867990 is a wasteful number, since it uses less digits than its factorization.

205867990 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 438071.

The product of its (nonzero) digits is 272160, while the sum is 46.

The square root of 205867990 is about 14348.1005711558. The cubic root of 205867990 is about 590.4678755446.

The spelling of 205867990 in words is "two hundred five million, eight hundred sixty-seven thousand, nine hundred ninety".