138408005 has 8 divisors (see below), whose sum is σ = 170140824. Its totient is φ = 108025600.

The previous prime is 138407993. The next prime is 138408047. The reversal of 138408005 is 500804831.

138408005 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It can be written as a sum of positive squares in 4 ways, for example, as 12945604 + 125462401 = 3598^2 + 11201^2 .

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

It is a de Polignac number, because none of the positive numbers 2^k-138408005 is a prime.

It is a Duffinian number.

It is a Curzon 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, 337376 + ... + 337785.

It is an arithmetic number, because the mean of its divisors is an integer number (21267603).

Almost surely, 2^138408005 is an apocalyptic number.

It is an amenable number.

138408005 is a deficient number, since it is larger than the sum of its proper divisors (31732819).

138408005 is an equidigital number, since it uses as much as digits as its factorization.

138408005 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 675207.

The product of its (nonzero) digits is 3840, while the sum is 29.

The square root of 138408005 is about 11764.6931536696. The cubic root of 138408005 is about 517.2737059717.

The spelling of 138408005 in words is "one hundred thirty-eight million, four hundred eight thousand, five".