138805009 has 8 divisors (see below), whose sum is σ = 158977728. Its totient is φ = 118718160.

The previous prime is 138805003. The next prime is 138805027. The reversal of 138805009 is 900508831.

138805009 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 138805009 - 2¹³ = 138796817 is a prime.

It is not an unprimeable number, because it can be changed into a prime (138805003) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 17962 + ... + 24499.

It is an arithmetic number, because the mean of its divisors is an integer number (19872216).

Almost surely, 2^138805009 is an apocalyptic number.

It is an amenable number.

138805009 is a deficient number, since it is larger than the sum of its proper divisors (20172719).

138805009 is an equidigital number, since it uses as much as digits as its factorization.

138805009 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 42935.

The product of its (nonzero) digits is 8640, while the sum is 34.

The square root of 138805009 is about 11781.5537600098. The cubic root of 138805009 is about 517.7678096042.

The spelling of 138805009 in words is "one hundred thirty-eight million, eight hundred five thousand, nine".