13566134561 has 6 divisors (see below), whose sum is σ = 15781013730. Its totient is φ = 11628115296.

The previous prime is 13566134557. The next prime is 13566134581. The reversal of 13566134561 is 16543166531.

It can be written as a sum of positive squares in only one way, i.e., 9243861025 + 4322273536 = 96145^2 + 65744^2 .

It is not a de Polignac number, because 13566134561 - 2² = 13566134557 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (13566134531) by changing a digit.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 138429896 + ... + 138429993.

It is an arithmetic number, because the mean of its divisors is an integer number (2630168955).

Almost surely, 2^13566134561 is an apocalyptic number.

It is an amenable number.

13566134561 is a deficient number, since it is larger than the sum of its proper divisors (2214879169).

13566134561 is an equidigital number, since it uses as much as digits as its factorization.

13566134561 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 276859903 (or 276859896 counting only the distinct ones).

The product of its digits is 194400, while the sum is 41.

The spelling of 13566134561 in words is "thirteen billion, five hundred sixty-six million, one hundred thirty-four thousand, five hundred sixty-one".