8120615905 has 4 divisors (see below), whose sum is σ = 9744739092. Its totient is φ = 6496492720.

The previous prime is 8120615897. The next prime is 8120615929. The reversal of 8120615905 is 5095160218.

8120615905 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

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 3017085184 + 5103530721 = 54928^2 + 71439^2 .

It is not a de Polignac number, because 8120615905 - 2³ = 8120615897 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, 812061586 + ... + 812061595.

It is an arithmetic number, because the mean of its divisors is an integer number (2436184773).

Almost surely, 2^8120615905 is an apocalyptic number.

It is an amenable number.

8120615905 is a deficient number, since it is larger than the sum of its proper divisors (1624123187).

8120615905 is a wasteful number, since it uses less digits than its factorization.

8120615905 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1624123186.

The product of its (nonzero) digits is 21600, while the sum is 37.

The square root of 8120615905 is about 90114.4600216858. The cubic root of 8120615905 is about 2010.0012297543.

The spelling of 8120615905 in words is "eight billion, one hundred twenty million, six hundred fifteen thousand, nine hundred five".