91128523 has 2 divisors, whose sum is σ = 91128524. Its totient is φ = 91128522.

The previous prime is 91128491. The next prime is 91128577. The reversal of 91128523 is 32582119.

It is a weak prime.

It is a cyclic number.

It is not a de Polignac number, because 91128523 - 2⁵ = 91128491 is a prime.

It is not a weakly prime, because it can be changed into another prime (91188523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 45564261 + 45564262.

It is an arithmetic number, because the mean of its divisors is an integer number (45564262).

Almost surely, 2^91128523 is an apocalyptic number.

91128523 is a deficient number, since it is larger than the sum of its proper divisors (1).

91128523 is an equidigital number, since it uses as much as digits as its factorization.

91128523 is an evil number, because the sum of its binary digits is even.

The product of its digits is 4320, while the sum is 31.

The square root of 91128523 is about 9546.1260729157. The cubic root of 91128523 is about 450.0057991022.

The spelling of 91128523 in words is "ninety-one million, one hundred twenty-eight thousand, five hundred twenty-three".