139105205 has 4 divisors (see below), whose sum is σ = 166926252. Its totient is φ = 111284160.

The previous prime is 139105201. The next prime is 139105229. The reversal of 139105205 is 502501931.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 39225169 + 99880036 = 6263^2 + 9994^2 .

It is not a de Polignac number, because 139105205 - 2² = 139105201 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (139105201) by changing a digit.

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 3 ways as a sum of consecutive naturals, for example, 13910516 + ... + 13910525.

It is an arithmetic number, because the mean of its divisors is an integer number (41731563).

Almost surely, 2^139105205 is an apocalyptic number.

It is an amenable number.

139105205 is a deficient number, since it is larger than the sum of its proper divisors (27821047).

139105205 is an equidigital number, since it uses as much as digits as its factorization.

139105205 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 27821046.

The product of its (nonzero) digits is 1350, while the sum is 26.

The square root of 139105205 is about 11794.2869644587. The cubic root of 139105205 is about 518.1408026472.

The spelling of 139105205 in words is "one hundred thirty-nine million, one hundred five thousand, two hundred five".