12387191065 has 4 divisors (see below), whose sum is σ = 14864629284. Its totient is φ = 9909752848.

The previous prime is 12387191027. The next prime is 12387191081. The reversal of 12387191065 is 56019178321.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 56019178321 = 157 ⋅356810053.

It can be written as a sum of positive squares in 2 ways, for example, as 9689842969 + 2697348096 = 98437^2 + 51936^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12387191065 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, 1238719102 + ... + 1238719111.

It is an arithmetic number, because the mean of its divisors is an integer number (3716157321).

Almost surely, 2^12387191065 is an apocalyptic number.

It is an amenable number.

12387191065 is a deficient number, since it is larger than the sum of its proper divisors (2477438219).

12387191065 is an equidigital number, since it uses as much as digits as its factorization.

12387191065 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2477438218.

The product of its (nonzero) digits is 90720, while the sum is 43.

The spelling of 12387191065 in words is "twelve billion, three hundred eighty-seven million, one hundred ninety-one thousand, sixty-five".