139709 has 2 divisors, whose sum is σ = 139710.
Its totient is φ = 139708.
The previous prime is 139703. The next prime is 139721. The reversal of 139709 is 907931.
139709 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.
It is a weak prime.
It can be written as a sum of positive squares in only one way, i.e., 136900 + 2809 = 370^2 + 53^2
It is a cyclic number.
It is not a de Polignac number, because 139709 - 212 = 135613 is a prime.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (139703) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 69854 + 69855.
It is an arithmetic number, because the mean of its divisors is an integer number (69855).
2139709 is an apocalyptic number.
It is an amenable number.
139709 is a deficient number, since it is larger than the sum of its proper divisors (1).
139709 is an equidigital number, since it uses as much as digits as its factorization.
139709 is an odious number, because the sum of its binary digits is odd.
The product of its (nonzero) digits is 1701, while the sum is 29.
The square root of 139709 is about 373.7766712892.
The cubic root of 139709 is about 51.8889394968.
Note that the first 3 decimals are identical.
It can be divided in two parts, 139 and 709, that added together give a palindrome (848).
The spelling of 139709 in words is "one hundred thirty-nine thousand, seven hundred nine".