91923393585421 has 2 divisors, whose sum is σ = 91923393585422. Its totient is φ = 91923393585420.

The previous prime is 91923393585377. The next prime is 91923393585461. The reversal of 91923393585421 is 12458539332919.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 72498174751396 + 19425218834025 = 8514586^2 + 4407405^2 .

It is a cyclic number.

It is not a de Polignac number, because 91923393585421 - 2³³ = 91914803650829 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91923393585461) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45961696792710 + 45961696792711.

It is an arithmetic number, because the mean of its divisors is an integer number (45961696792711).

Almost surely, 2^{91923393585421} is an apocalyptic number.

It is an amenable number.

91923393585421 is a deficient number, since it is larger than the sum of its proper divisors (1).

91923393585421 is an equidigital number, since it uses as much as digits as its factorization.

91923393585421 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 62985600, while the sum is 64.

The spelling of 91923393585421 in words is "ninety-one trillion, nine hundred twenty-three billion, three hundred ninety-three million, five hundred eighty-five thousand, four hundred twenty-one".