91355632261 has 2 divisors, whose sum is σ = 91355632262. Its totient is φ = 91355632260.

The previous prime is 91355632243. The next prime is 91355632289. The reversal of 91355632261 is 16223655319.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 61749268036 + 29606364225 = 248494^2 + 172065^2 .

It is an emirp because it is prime and its reverse (16223655319) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91355632261 - 2⁵ = 91355632229 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91355632201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45677816130 + 45677816131.

It is an arithmetic number, because the mean of its divisors is an integer number (45677816131).

Almost surely, 2^91355632261 is an apocalyptic number.

It is an amenable number.

91355632261 is a deficient number, since it is larger than the sum of its proper divisors (1).

91355632261 is an equidigital number, since it uses as much as digits as its factorization.

91355632261 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 291600, while the sum is 43.

The spelling of 91355632261 in words is "ninety-one billion, three hundred fifty-five million, six hundred thirty-two thousand, two hundred sixty-one".