691846815811 has 2 divisors, whose sum is σ = 691846815812. Its totient is φ = 691846815810.

The previous prime is 691846815791. The next prime is 691846815827. The reversal of 691846815811 is 118518648196.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 691846815811 - 2⁹ = 691846815299 is a prime.

It is not a weakly prime, because it can be changed into another prime (691846815911) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345923407905 + 345923407906.

It is an arithmetic number, because the mean of its divisors is an integer number (345923407906).

Almost surely, 2^691846815811 is an apocalyptic number.

691846815811 is a deficient number, since it is larger than the sum of its proper divisors (1).

691846815811 is an equidigital number, since it uses as much as digits as its factorization.

691846815811 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 3317760, while the sum is 58.

The spelling of 691846815811 in words is "six hundred ninety-one billion, eight hundred forty-six million, eight hundred fifteen thousand, eight hundred eleven".