91128459 has 4 divisors (see below), whose sum is σ = 121504616. Its totient is φ = 60752304.

The previous prime is 91128451. The next prime is 91128463. The reversal of 91128459 is 95482119.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 91128459 - 2³ = 91128451 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91128451) 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 in 3 ways as a sum of consecutive naturals, for example, 15188074 + ... + 15188079.

It is an arithmetic number, because the mean of its divisors is an integer number (30376154).

Almost surely, 2^91128459 is an apocalyptic number.

91128459 is a deficient number, since it is larger than the sum of its proper divisors (30376157).

91128459 is a wasteful number, since it uses less digits than its factorization.

91128459 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 30376156.

The product of its digits is 25920, while the sum is 39.

The square root of 91128459 is about 9546.1227207699. The cubic root of 91128459 is about 450.0056937551.

It can be divided in two parts, 9112 and 8459, that added together give a palindrome (17571).

The spelling of 91128459 in words is "ninety-one million, one hundred twenty-eight thousand, four hundred fifty-nine".