1691307567841 has 2 divisors, whose sum is σ = 1691307567842. Its totient is φ = 1691307567840.

The previous prime is 1691307567827. The next prime is 1691307567863. The reversal of 1691307567841 is 1487657031961.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 1557641283025 + 133666284816 = 1248055^2 + 365604^2 .

It is a cyclic number.

It is not a de Polignac number, because 1691307567841 - 2¹⁷ = 1691307436769 is a prime.

It is not a weakly prime, because it can be changed into another prime (1691307567811) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 845653783920 + 845653783921.

It is an arithmetic number, because the mean of its divisors is an integer number (845653783921).

Almost surely, 2^{1691307567841} is an apocalyptic number.

It is an amenable number.

1691307567841 is a deficient number, since it is larger than the sum of its proper divisors (1).

1691307567841 is an equidigital number, since it uses as much as digits as its factorization.

1691307567841 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 7620480, while the sum is 58.

The spelling of 1691307567841 in words is "one trillion, six hundred ninety-one billion, three hundred seven million, five hundred sixty-seven thousand, eight hundred forty-one".