139909 has 16 divisors (see below), whose sum is σ = 184320. Its totient is φ = 102960.

The previous prime is 139907. The next prime is 139921. The reversal of 139909 is 909931.

It is not a de Polignac number, because 139909 - 2¹ = 139907 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 (139901) 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, 1732 + ... + 1810.

It is an arithmetic number, because the mean of its divisors is an integer number (11520).

2¹³⁹⁹⁰⁹ is an apocalyptic number.

It is an amenable number.

139909 is a deficient number, since it is larger than the sum of its proper divisors (44411).

139909 is a wasteful number, since it uses less digits than its factorization.

139909 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 120.

The product of its (nonzero) digits is 2187, while the sum is 31.

The square root of 139909 is about 374.0441150453. The cubic root of 139909 is about 51.9136881762.

The spelling of 139909 in words is "one hundred thirty-nine thousand, nine hundred nine".