8139561 has 16 divisors (see below), whose sum is σ = 11129664. Its totient is φ = 5289984.

The previous prime is 8139553. The next prime is 8139563. The reversal of 8139561 is 1659318.

8139561 is digitally balanced in base 3, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 8139561 - 2³ = 8139553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (8139563) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 23985 + ... + 24321.

It is an arithmetic number, because the mean of its divisors is an integer number (695604).

Almost surely, 2^8139561 is an apocalyptic number.

It is an amenable number.

8139561 is a deficient number, since it is larger than the sum of its proper divisors (2990103).

8139561 is a wasteful number, since it uses less digits than its factorization.

8139561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 520.

The product of its digits is 6480, while the sum is 33.

The square root of 8139561 is about 2852.9915877899. The cubic root of 8139561 is about 201.1563101834.

The spelling of 8139561 in words is "eight million, one hundred thirty-nine thousand, five hundred sixty-one".