205421312 has 72 divisors (see below), whose sum is σ = 435985200. Its totient is φ = 96325632.

The previous prime is 205421311. The next prime is 205421327. The reversal of 205421312 is 213124502.

It is not an unprimeable number, because it can be changed into a prime (205421311) 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 7 ways as a sum of consecutive naturals, for example, 763514 + ... + 763782.

It is an arithmetic number, because the mean of its divisors is an integer number (6055350).

Almost surely, 2^205421312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205421312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (217992600).

205421312 is an abundant number, since it is smaller than the sum of its proper divisors (230563888).

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

205421312 is a wasteful number, since it uses less digits than its factorization.

205421312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 461 (or 447 counting only the distinct ones).

The product of its (nonzero) digits is 480, while the sum is 20.

The square root of 205421312 is about 14332.5263648807. The cubic root of 205421312 is about 590.0405143107.

Adding to 205421312 its reverse (213124502), we get a palindrome (418545814).

The spelling of 205421312 in words is "two hundred five million, four hundred twenty-one thousand, three hundred twelve".