12542540666065 has 4 divisors (see below), whose sum is σ = 15051048799284. Its totient is φ = 10034032532848.

The previous prime is 12542540666017. The next prime is 12542540666129. The reversal of 12542540666065 is 56066604524521.

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 1604095707841 + 10938444958224 = 1266529^2 + 3307332^2 .

It is a cyclic number.

It is not a de Polignac number, because 12542540666065 - 2¹³ = 12542540657873 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, 1254254066602 + ... + 1254254066611.

It is an arithmetic number, because the mean of its divisors is an integer number (3762762199821).

Almost surely, 2^{12542540666065} is an apocalyptic number.

It is an amenable number.

12542540666065 is a deficient number, since it is larger than the sum of its proper divisors (2508508133219).

12542540666065 is an equidigital number, since it uses as much as digits as its factorization.

12542540666065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2508508133218.

The product of its (nonzero) digits is 10368000, while the sum is 52.

The spelling of 12542540666065 in words is "twelve trillion, five hundred forty-two billion, five hundred forty million, six hundred sixty-six thousand, sixty-five".