831566643961 has 2 divisors, whose sum is σ = 831566643962. Its totient is φ = 831566643960.

The previous prime is 831566643953. The next prime is 831566643979. The reversal of 831566643961 is 169346665138.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 610531263225 + 221035380736 = 781365^2 + 470144^2 .

It is a cyclic number.

It is not a de Polignac number, because 831566643961 - 2³ = 831566643953 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 831566643896 and 831566643905.

It is not a weakly prime, because it can be changed into another prime (831566653961) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 415783321980 + 415783321981.

It is an arithmetic number, because the mean of its divisors is an integer number (415783321981).

Almost surely, 2^831566643961 is an apocalyptic number.

It is an amenable number.

831566643961 is a deficient number, since it is larger than the sum of its proper divisors (1).

831566643961 is an equidigital number, since it uses as much as digits as its factorization.

831566643961 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 16796160, while the sum is 58.

The spelling of 831566643961 in words is "eight hundred thirty-one billion, five hundred sixty-six million, six hundred forty-three thousand, nine hundred sixty-one".