81740998193 has 2 divisors, whose sum is σ = 81740998194. Its totient is φ = 81740998192.

The previous prime is 81740998169. The next prime is 81740998211. The reversal of 81740998193 is 39189904718.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 80776460944 + 964537249 = 284212^2 + 31057^2 .

It is a cyclic number.

It is not a de Polignac number, because 81740998193 - 2¹⁴ = 81740981809 is a prime.

It is not a weakly prime, because it can be changed into another prime (81740998793) 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, 40870499096 + 40870499097.

It is an arithmetic number, because the mean of its divisors is an integer number (40870499097).

Almost surely, 2^81740998193 is an apocalyptic number.

It is an amenable number.

81740998193 is a deficient number, since it is larger than the sum of its proper divisors (1).

81740998193 is an equidigital number, since it uses as much as digits as its factorization.

81740998193 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 3919104, while the sum is 59.

The spelling of 81740998193 in words is "eighty-one billion, seven hundred forty million, nine hundred ninety-eight thousand, one hundred ninety-three".