205915140 has 72 divisors (see below), whose sum is σ = 626360280. Its totient is φ = 54756864.

The previous prime is 205915139. The next prime is 205915181. The reversal of 205915140 is 41519502.

205915140 is a `hidden beast` number, since 20 + 591 + 51 + 4 + 0 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 83503044 + 122412096 = 9138^2 + 11064^2 .

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (7) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 72222 + ... + 75018.

Almost surely, 2^205915140 is an apocalyptic number.

205915140 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 205915140, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (313180140).

205915140 is an abundant number, since it is smaller than the sum of its proper divisors (420445140).

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

205915140 is a wasteful number, since it uses less digits than its factorization.

205915140 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3221 (or 3216 counting only the distinct ones).

The product of its (nonzero) digits is 1800, while the sum is 27.

The square root of 205915140 is about 14349.7435517155. The cubic root of 205915140 is about 590.5129504413.

The spelling of 205915140 in words is "two hundred five million, nine hundred fifteen thousand, one hundred forty".