205242540 has 48 divisors (see below), whose sum is σ = 582785280. Its totient is φ = 53959360.

The previous prime is 205242539. The next prime is 205242559. The reversal of 205242540 is 45242502.

It is a happy number.

It is a self number, because there is not a number n which added to its sum of digits gives 205242540.

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 15 ways as a sum of consecutive naturals, for example, 19830 + ... + 28349.

It is an arithmetic number, because the mean of its divisors is an integer number (12141360).

Almost surely, 2^205242540 is an apocalyptic number.

205242540 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

205242540 is an abundant number, since it is smaller than the sum of its proper divisors (377542740).

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

205242540 is a wasteful number, since it uses less digits than its factorization.

205242540 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48262 (or 48260 counting only the distinct ones).

The product of its (nonzero) digits is 3200, while the sum is 24.

The square root of 205242540 is about 14326.2884237335. The cubic root of 205242540 is about 589.8692997856.

The spelling of 205242540 in words is "two hundred five million, two hundred forty-two thousand, five hundred forty".