91939321823 has 2 divisors, whose sum is σ = 91939321824. Its totient is φ = 91939321822.

The previous prime is 91939321769. The next prime is 91939321849. The reversal of 91939321823 is 32812393919.

It is a strong prime.

It is a cyclic number.

It is not a de Polignac number, because 91939321823 - 2⁶ = 91939321759 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91939324823) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45969660911 + 45969660912.

It is an arithmetic number, because the mean of its divisors is an integer number (45969660912).

Almost surely, 2^91939321823 is an apocalyptic number.

91939321823 is a deficient number, since it is larger than the sum of its proper divisors (1).

91939321823 is an equidigital number, since it uses as much as digits as its factorization.

91939321823 is an evil number, because the sum of its binary digits is even.

The product of its digits is 629856, while the sum is 50.

The spelling of 91939321823 in words is "ninety-one billion, nine hundred thirty-nine million, three hundred twenty-one thousand, eight hundred twenty-three".