91111123 has 2 divisors, whose sum is σ = 91111124. Its totient is φ = 91111122.

The previous prime is 91111093. The next prime is 91111129. The reversal of 91111123 is 32111119.

It is a strong prime.

It is an emirp because it is prime and its reverse (32111119) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 91111123 - 2⁵ = 91111091 is a prime.

It is a super-2 number, since 2×91111123² = 16602473468642258, which contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 91111123.

It is not a weakly prime, because it can be changed into another prime (91111129) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45555561 + 45555562.

It is an arithmetic number, because the mean of its divisors is an integer number (45555562).

Almost surely, 2^91111123 is an apocalyptic number.

91111123 is a deficient number, since it is larger than the sum of its proper divisors (1).

91111123 is an equidigital number, since it uses as much as digits as its factorization.

91111123 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 54, while the sum is 19.

The square root of 91111123 is about 9545.2146649512. The cubic root of 91111123 is about 449.9771560420.

The spelling of 91111123 in words is "ninety-one million, one hundred eleven thousand, one hundred twenty-three".