83191661893 has 2 divisors, whose sum is σ = 83191661894. Its totient is φ = 83191661892.

The previous prime is 83191661887. The next prime is 83191661923. The reversal of 83191661893 is 39816619138.

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., 78597804609 + 4593857284 = 280353^2 + 67778^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-83191661893 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (83191661393) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 41595830946 + 41595830947.

It is an arithmetic number, because the mean of its divisors is an integer number (41595830947).

Almost surely, 2^83191661893 is an apocalyptic number.

It is an amenable number.

83191661893 is a deficient number, since it is larger than the sum of its proper divisors (1).

83191661893 is an equidigital number, since it uses as much as digits as its factorization.

83191661893 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 1679616, while the sum is 55.

The spelling of 83191661893 in words is "eighty-three billion, one hundred ninety-one million, six hundred sixty-one thousand, eight hundred ninety-three".