91205857229 has 2 divisors, whose sum is σ = 91205857230. Its totient is φ = 91205857228.

The previous prime is 91205857181. The next prime is 91205857247. The reversal of 91205857229 is 92275850219.

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., 63357924100 + 27847933129 = 251710^2 + 166877^2 .

It is a cyclic number.

It is not a de Polignac number, because 91205857229 - 2¹² = 91205853133 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (91205857279) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45602928614 + 45602928615.

It is an arithmetic number, because the mean of its divisors is an integer number (45602928615).

Almost surely, 2^91205857229 is an apocalyptic number.

It is an amenable number.

91205857229 is a deficient number, since it is larger than the sum of its proper divisors (1).

91205857229 is an equidigital number, since it uses as much as digits as its factorization.

91205857229 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 907200, while the sum is 50.

The spelling of 91205857229 in words is "ninety-one billion, two hundred five million, eight hundred fifty-seven thousand, two hundred twenty-nine".