91684391189 has 2 divisors, whose sum is σ = 91684391190. Its totient is φ = 91684391188.

The previous prime is 91684391147. The next prime is 91684391261. The reversal of 91684391189 is 98119348619.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 90590766289 + 1093624900 = 300983^2 + 33070^2 .

It is a cyclic number.

It is not a de Polignac number, because 91684391189 - 2⁸ = 91684390933 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91684391989) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45842195594 + 45842195595.

It is an arithmetic number, because the mean of its divisors is an integer number (45842195595).

Almost surely, 2^91684391189 is an apocalyptic number.

It is an amenable number.

91684391189 is a deficient number, since it is larger than the sum of its proper divisors (1).

91684391189 is an equidigital number, since it uses as much as digits as its factorization.

91684391189 is an evil number, because the sum of its binary digits is even.

The product of its digits is 3359232, while the sum is 59.

The spelling of 91684391189 in words is "ninety-one billion, six hundred eighty-four million, three hundred ninety-one thousand, one hundred eighty-nine".