205638312 has 32 divisors (see below), whose sum is σ = 560832480. Its totient is φ = 62314560.

The previous prime is 205638287. The next prime is 205638317. The reversal of 205638312 is 213836502.

It is a self number, because there is not a number n which added to its sum of digits gives 205638312.

It is not an unprimeable number, because it can be changed into a prime (205638317) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 389203 + ... + 389730.

It is an arithmetic number, because the mean of its divisors is an integer number (17526015).

Almost surely, 2^205638312 is an apocalyptic number.

205638312 is a gapful number since it is divisible by the number (22) formed by its first and last digit.

It is an amenable number.

205638312 is an abundant number, since it is smaller than the sum of its proper divisors (355194168).

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

205638312 is a wasteful number, since it uses less digits than its factorization.

205638312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 778953 (or 778949 counting only the distinct ones).

The product of its (nonzero) digits is 8640, while the sum is 30.

The square root of 205638312 is about 14340.0945603577. The cubic root of 205638312 is about 590.2482073547.

The spelling of 205638312 in words is "two hundred five million, six hundred thirty-eight thousand, three hundred twelve".