691546865461 has 2 divisors, whose sum is σ = 691546865462. Its totient is φ = 691546865460.

The previous prime is 691546865441. The next prime is 691546865491. The reversal of 691546865461 is 164568645196.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 672122868561 + 19423996900 = 819831^2 + 139370^2 .

It is a cyclic number.

It is not a de Polignac number, because 691546865461 - 2⁷ = 691546865333 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 691546865461.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (691546865441) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 345773432730 + 345773432731.

It is an arithmetic number, because the mean of its divisors is an integer number (345773432731).

Almost surely, 2^691546865461 is an apocalyptic number.

It is an amenable number.

691546865461 is a deficient number, since it is larger than the sum of its proper divisors (1).

691546865461 is an equidigital number, since it uses as much as digits as its factorization.

691546865461 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 37324800, while the sum is 61.

The spelling of 691546865461 in words is "six hundred ninety-one billion, five hundred forty-six million, eight hundred sixty-five thousand, four hundred sixty-one".