13191621066809 has 2 divisors, whose sum is σ = 13191621066810. Its totient is φ = 13191621066808.

The previous prime is 13191621066797. The next prime is 13191621066839. The reversal of 13191621066809 is 90866012619131.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13026346295209 + 165274771600 = 3609203^2 + 406540^2 .

It is a cyclic number.

It is not a de Polignac number, because 13191621066809 - 2⁸ = 13191621066553 is a prime.

It is not a weakly prime, because it can be changed into another prime (13191621066839) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6595810533404 + 6595810533405.

It is an arithmetic number, because the mean of its divisors is an integer number (6595810533405).

Almost surely, 2^{13191621066809} is an apocalyptic number.

It is an amenable number.

13191621066809 is a deficient number, since it is larger than the sum of its proper divisors (1).

13191621066809 is an equidigital number, since it uses as much as digits as its factorization.

13191621066809 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 839808, while the sum is 53.

The spelling of 13191621066809 in words is "thirteen trillion, one hundred ninety-one billion, six hundred twenty-one million, sixty-six thousand, eight hundred nine".