12660715421 has 2 divisors, whose sum is σ = 12660715422. Its totient is φ = 12660715420.

The previous prime is 12660715393. The next prime is 12660715433. The reversal of 12660715421 is 12451706621.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 10514246521 + 2146468900 = 102539^2 + 46330^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-12660715421 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (12660715021) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6330357710 + 6330357711.

It is an arithmetic number, because the mean of its divisors is an integer number (6330357711).

Almost surely, 2^12660715421 is an apocalyptic number.

It is an amenable number.

12660715421 is a deficient number, since it is larger than the sum of its proper divisors (1).

12660715421 is an equidigital number, since it uses as much as digits as its factorization.

12660715421 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 20160, while the sum is 35.

The spelling of 12660715421 in words is "twelve billion, six hundred sixty million, seven hundred fifteen thousand, four hundred twenty-one".