138837805 has 8 divisors (see below), whose sum is σ = 166785912. Its totient is φ = 110949888.

The previous prime is 138837799. The next prime is 138837817. The reversal of 138837805 is 508738831.

It can be written as a sum of positive squares in 4 ways, for example, as 35652841 + 103184964 = 5971^2 + 10158^2 .

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 138837805 - 2⁵ = 138837773 is a prime.

It is a Duffinian number.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 9804 + ... + 19333.

It is an arithmetic number, because the mean of its divisors is an integer number (20848239).

Almost surely, 2^138837805 is an apocalyptic number.

It is an amenable number.

138837805 is a deficient number, since it is larger than the sum of its proper divisors (27948107).

138837805 is an equidigital number, since it uses as much as digits as its factorization.

138837805 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30095.

The product of its (nonzero) digits is 161280, while the sum is 43.

The square root of 138837805 is about 11782.9455145986. The cubic root of 138837805 is about 517.8085847318.

It can be divided in two parts, 1388 and 37805, that added together give a palindrome (39193).

The spelling of 138837805 in words is "one hundred thirty-eight million, eight hundred thirty-seven thousand, eight hundred five".