139205305 has 16 divisors (see below), whose sum is σ = 179585280. Its totient is φ = 103254912.

The previous prime is 139205293. The next prime is 139205309. The reversal of 139205305 is 503502931.

It is a cyclic number.

It is not a de Polignac number, because 139205305 - 2⁵ = 139205273 is a prime.

It is not an unprimeable number, because it can be changed into a prime (139205309) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 11124 + ... + 20053.

It is an arithmetic number, because the mean of its divisors is an integer number (11224080).

Almost surely, 2^139205305 is an apocalyptic number.

It is an amenable number.

139205305 is a deficient number, since it is larger than the sum of its proper divisors (40379975).

139205305 is a wasteful number, since it uses less digits than its factorization.

139205305 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 31248.

The product of its (nonzero) digits is 4050, while the sum is 28.

The square root of 139205305 is about 11798.5297812905. The cubic root of 139205305 is about 518.2650574236.

The spelling of 139205305 in words is "one hundred thirty-nine million, two hundred five thousand, three hundred five".