91334221021 has 2 divisors, whose sum is σ = 91334221022. Its totient is φ = 91334221020.

The previous prime is 91334221003. The next prime is 91334221031. The reversal of 91334221021 is 12012243319.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 68898375225 + 22435845796 = 262485^2 + 149786^2 .

It is a cyclic number.

It is not a de Polignac number, because 91334221021 - 2¹¹ = 91334218973 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91334221031) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45667110510 + 45667110511.

It is an arithmetic number, because the mean of its divisors is an integer number (45667110511).

Almost surely, 2^91334221021 is an apocalyptic number.

It is an amenable number.

91334221021 is a deficient number, since it is larger than the sum of its proper divisors (1).

91334221021 is an equidigital number, since it uses as much as digits as its factorization.

91334221021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2592, while the sum is 28.

The spelling of 91334221021 in words is "ninety-one billion, three hundred thirty-four million, two hundred twenty-one thousand, twenty-one".