91859695813 has 2 divisors, whose sum is σ = 91859695814. Its totient is φ = 91859695812.

The previous prime is 91859695799. The next prime is 91859695817. The reversal of 91859695813 is 31859695819.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 77675362209 + 14184333604 = 278703^2 + 119098^2 .

It is a cyclic number.

It is not a de Polignac number, because 91859695813 - 2²¹ = 91857598661 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91859695817) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45929847906 + 45929847907.

It is an arithmetic number, because the mean of its divisors is an integer number (45929847907).

Almost surely, 2^91859695813 is an apocalyptic number.

It is an amenable number.

91859695813 is a deficient number, since it is larger than the sum of its proper divisors (1).

91859695813 is an equidigital number, since it uses as much as digits as its factorization.

91859695813 is an evil number, because the sum of its binary digits is even.

The product of its digits is 20995200, while the sum is 64.

The spelling of 91859695813 in words is "ninety-one billion, eight hundred fifty-nine million, six hundred ninety-five thousand, eight hundred thirteen".