91165121 has 2 divisors, whose sum is σ = 91165122. Its totient is φ = 91165120.

The previous prime is 91165043. The next prime is 91165153. The reversal of 91165121 is 12156119.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 71487025 + 19678096 = 8455^2 + 4436^2 .

It is an emirp because it is prime and its reverse (12156119) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91165121 - 2¹⁰ = 91164097 is a prime.

It is a super-2 number, since 2×91165121² = 16622158573889282, which contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (91165421) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45582560 + 45582561.

It is an arithmetic number, because the mean of its divisors is an integer number (45582561).

Almost surely, 2^91165121 is an apocalyptic number.

It is an amenable number.

91165121 is a deficient number, since it is larger than the sum of its proper divisors (1).

91165121 is an equidigital number, since it uses as much as digits as its factorization.

91165121 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 540, while the sum is 26.

The square root of 91165121 is about 9548.0427837332. The cubic root of 91165121 is about 450.0660331082.

The spelling of 91165121 in words is "ninety-one million, one hundred sixty-five thousand, one hundred twenty-one".