137909 has 2 divisors, whose sum is σ = 137910.
Its totient is φ = 137908.
The previous prime is 137873. The next prime is 137911. The reversal of 137909 is 909731.
137909 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.
It is a strong prime.
It can be written as a sum of positive squares in only one way, i.e., 103684 + 34225 = 322^2 + 185^2
It is an emirp because it is prime and its reverse (909731) is a distict prime.
It is a cyclic number.
It is not a de Polignac number, because 137909 - 28 = 137653 is a prime.
Together with 137911, it forms a pair of twin primes.
It is a Chen prime.
It is a plaindrome in base 15.
It is a congruent number.
It is not a weakly prime, because it can be changed into another prime (137999) by changing a digit.
It is a polite number, since it can be written as a sum of consecutive naturals, namely, 68954 + 68955.
It is an arithmetic number, because the mean of its divisors is an integer number (68955).
2137909 is an apocalyptic number.
It is an amenable number.
137909 is a deficient number, since it is larger than the sum of its proper divisors (1).
137909 is an equidigital number, since it uses as much as digits as its factorization.
137909 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 137909 is about 371.3610103390.
The cubic root of 137909 is about 51.6651311834.
The spelling of 137909 in words is "one hundred thirty-seven thousand, nine hundred nine".