39538806399865 has 4 divisors (see below), whose sum is σ = 47446567679844. Its totient is φ = 31631045119888.

The previous prime is 39538806399793. The next prime is 39538806399893. The reversal of 39538806399865 is 56899360883593.

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 10770086531961 + 28768719867904 = 3281781^2 + 5363648^2 .

It is a cyclic number.

It is not a de Polignac number, because 39538806399865 - 2⁹ = 39538806399353 is a prime.

It is a Duffinian number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3953880639982 + ... + 3953880639991.

It is an arithmetic number, because the mean of its divisors is an integer number (11861641919961).

Almost surely, 2^{39538806399865} is an apocalyptic number.

It is an amenable number.

39538806399865 is a deficient number, since it is larger than the sum of its proper divisors (7907761279979).

39538806399865 is an equidigital number, since it uses as much as digits as its factorization.

39538806399865 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7907761279978.

The product of its (nonzero) digits is 9069926400, while the sum is 82.

The spelling of 39538806399865 in words is "thirty-nine trillion, five hundred thirty-eight billion, eight hundred six million, three hundred ninety-nine thousand, eight hundred sixty-five".