12186606661 has 2 divisors, whose sum is σ = 12186606662. Its totient is φ = 12186606660.

The previous prime is 12186606643. The next prime is 12186606697. The reversal of 12186606661 is 16660668121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8594402436 + 3592204225 = 92706^2 + 59935^2 .

It is an emirp because it is prime and its reverse (16660668121) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12186606661 - 2²³ = 12178218053 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12186606361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6093303330 + 6093303331.

It is an arithmetic number, because the mean of its divisors is an integer number (6093303331).

Almost surely, 2^12186606661 is an apocalyptic number.

It is an amenable number.

12186606661 is a deficient number, since it is larger than the sum of its proper divisors (1).

12186606661 is an equidigital number, since it uses as much as digits as its factorization.

12186606661 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 124416, while the sum is 43.

The spelling of 12186606661 in words is "twelve billion, one hundred eighty-six million, six hundred six thousand, six hundred sixty-one".