12516433691 has 2 divisors, whose sum is σ = 12516433692. Its totient is φ = 12516433690.

The previous prime is 12516433661. The next prime is 12516433697. The reversal of 12516433691 is 19633461521.

It is a happy number.

It is a strong prime.

It is an emirp because it is prime and its reverse (19633461521) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 12516433691 - 2³⁰ = 11442691867 is a prime.

It is a super-2 number, since 2×12516433691² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (12516433697) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6258216845 + 6258216846.

It is an arithmetic number, because the mean of its divisors is an integer number (6258216846).

Almost surely, 2^12516433691 is an apocalyptic number.

12516433691 is a deficient number, since it is larger than the sum of its proper divisors (1).

12516433691 is an equidigital number, since it uses as much as digits as its factorization.

12516433691 is an evil number, because the sum of its binary digits is even.

The product of its digits is 116640, while the sum is 41.

The spelling of 12516433691 in words is "twelve billion, five hundred sixteen million, four hundred thirty-three thousand, six hundred ninety-one".