205212210 has 64 divisors (see below), whose sum is σ = 587354112. Its totient is φ = 44865216.

The previous prime is 205212193. The next prime is 205212239. The reversal of 205212210 is 12212502.

It is a super-2 number, since 2×205212210² = 84224102266168200, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 205212210.

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 31 ways as a sum of consecutive naturals, for example, 16414 + ... + 26073.

It is an arithmetic number, because the mean of its divisors is an integer number (9177408).

Almost surely, 2^205212210 is an apocalyptic number.

205212210 is an abundant number, since it is smaller than the sum of its proper divisors (382141902).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

205212210 is a wasteful number, since it uses less digits than its factorization.

205212210 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 42527.

The product of its (nonzero) digits is 80, while the sum is 15.

The square root of 205212210 is about 14325.2298410881. The cubic root of 205212210 is about 589.8402421039.

Adding to 205212210 its reverse (12212502), we get a palindrome (217424712).

The spelling of 205212210 in words is "two hundred five million, two hundred twelve thousand, two hundred ten".