138017609 has 4 divisors (see below), whose sum is σ = 138718404. Its totient is φ = 137316816.

The previous prime is 138017597. The next prime is 138017617. The reversal of 138017609 is 906710831.

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 134676025 + 3341584 = 11605^2 + 1828^2 .

It is a cyclic number.

It is not a de Polignac number, because 138017609 - 2²⁴ = 121240393 is a prime.

It is a super-3 number, since 3×138017609³ (a number of 25 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (138017639) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 350102 + ... + 350495.

It is an arithmetic number, because the mean of its divisors is an integer number (34679601).

Almost surely, 2^138017609 is an apocalyptic number.

It is an amenable number.

138017609 is a deficient number, since it is larger than the sum of its proper divisors (700795).

138017609 is an equidigital number, since it uses as much as digits as its factorization.

138017609 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 700794.

The product of its (nonzero) digits is 9072, while the sum is 35.

The square root of 138017609 is about 11748.0895893758. The cubic root of 138017609 is about 516.7869042860.

The spelling of 138017609 in words is "one hundred thirty-eight million, seventeen thousand, six hundred nine".