205361640 has 96 divisors (see below), whose sum is σ = 728114400. Its totient is φ = 49783680.

The previous prime is 205361623. The next prime is 205361647. The reversal of 205361640 is 46163502.

205361640 is a `hidden beast` number, since 2 + 0 + 5 + 3 + 616 + 40 = 666.

205361640 is digitally balanced in base 2 and base 3, because in such bases it contains all the possibile digits an equal number of times.

It is not an unprimeable number, because it can be changed into a prime (205361647) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 21970 + ... + 29889.

It is an arithmetic number, because the mean of its divisors is an integer number (7584525).

Almost surely, 2^205361640 is an apocalyptic number.

205361640 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205361640 is an abundant number, since it is smaller than the sum of its proper divisors (522752760).

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

205361640 is a wasteful number, since it uses less digits than its factorization.

205361640 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51887 (or 51880 counting only the distinct ones).

The product of its (nonzero) digits is 4320, while the sum is 27.

The square root of 205361640 is about 14330.4445150875. Note that the first 3 decimals coincide. The cubic root of 205361640 is about 589.9833759560.

The spelling of 205361640 in words is "two hundred five million, three hundred sixty-one thousand, six hundred forty".