12615748661 has 2 divisors, whose sum is σ = 12615748662. Its totient is φ = 12615748660.

The previous prime is 12615748657. The next prime is 12615748711. The reversal of 12615748661 is 16684751621.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8778565636 + 3837183025 = 93694^2 + 61945^2 .

It is a cyclic number.

It is not a de Polignac number, because 12615748661 - 2² = 12615748657 is a prime.

It is a super-2 number, since 2×12615748661² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12615748361) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6307874330 + 6307874331.

It is an arithmetic number, because the mean of its divisors is an integer number (6307874331).

Almost surely, 2^12615748661 is an apocalyptic number.

It is an amenable number.

12615748661 is a deficient number, since it is larger than the sum of its proper divisors (1).

12615748661 is an equidigital number, since it uses as much as digits as its factorization.

12615748661 is an evil number, because the sum of its binary digits is even.

The product of its digits is 483840, while the sum is 47.

The spelling of 12615748661 in words is "twelve billion, six hundred fifteen million, seven hundred forty-eight thousand, six hundred sixty-one".