139605605 has 4 divisors (see below), whose sum is σ = 167526732. Its totient is φ = 111684480.

The previous prime is 139605593. The next prime is 139605647. The reversal of 139605605 is 506506931.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 506506931 = 7 ⋅72358133.

It can be written as a sum of positive squares in 2 ways, for example, as 30758116 + 108847489 = 5546^2 + 10433^2 .

It is not a de Polignac number, because 139605605 - 2²² = 135411301 is a prime.

It is a Duffinian number.

It is a Curzon number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13960556 + ... + 13960565.

It is an arithmetic number, because the mean of its divisors is an integer number (41881683).

Almost surely, 2^139605605 is an apocalyptic number.

It is an amenable number.

139605605 is a deficient number, since it is larger than the sum of its proper divisors (27921127).

139605605 is an equidigital number, since it uses as much as digits as its factorization.

139605605 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27921126.

The product of its (nonzero) digits is 24300, while the sum is 35.

The square root of 139605605 is about 11815.4815813830. The cubic root of 139605605 is about 518.7613578584.

The spelling of 139605605 in words is "one hundred thirty-nine million, six hundred five thousand, six hundred five".