205715139 has 32 divisors (see below), whose sum is σ = 322122240. Its totient is φ = 114331392.

The previous prime is 205715129. The next prime is 205715143. The reversal of 205715139 is 931517502.

205715139 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 205715139 - 2⁹ = 205714627 is a prime.

It is not an unprimeable number, because it can be changed into a prime (205715129) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 369049 + ... + 369605.

It is an arithmetic number, because the mean of its divisors is an integer number (10066320).

Almost surely, 2^205715139 is an apocalyptic number.

205715139 is a deficient number, since it is larger than the sum of its proper divisors (116407101).

205715139 is a wasteful number, since it uses less digits than its factorization.

205715139 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1019.

The product of its (nonzero) digits is 9450, while the sum is 33.

The square root of 205715139 is about 14342.7730582339. The cubic root of 205715139 is about 590.3217042832.

The spelling of 205715139 in words is "two hundred five million, seven hundred fifteen thousand, one hundred thirty-nine".