205398930 has 256 divisors, whose sum is σ = 627056640. Its totient is φ = 42393600.

The previous prime is 205398929. The next prime is 205398937. The reversal of 205398930 is 39893502.

It is a Curzon number.

It is not an unprimeable number, because it can be changed into a prime (205398937) 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 127 ways as a sum of consecutive naturals, for example, 4370167 + ... + 4370213.

It is an arithmetic number, because the mean of its divisors is an integer number (2449440).

Almost surely, 2^205398930 is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205398930, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (313528320).

205398930 is an abundant number, since it is smaller than the sum of its proper divisors (421657710).

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

205398930 is a wasteful number, since it uses less digits than its factorization.

205398930 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 145.

The product of its (nonzero) digits is 58320, while the sum is 39.

The square root of 205398930 is about 14331.7455322093. The cubic root of 205398930 is about 590.0190839370.

The spelling of 205398930 in words is "two hundred five million, three hundred ninety-eight thousand, nine hundred thirty".