91288769 has 16 divisors (see below), whose sum is σ = 110713344. Its totient is φ = 74131200.

The previous prime is 91288739. The next prime is 91288783. The reversal of 91288769 is 96788219.

It is not a de Polignac number, because 91288769 - 2²⁰ = 90240193 is a prime.

It is a super-2 number, since 2×91288769² = 16667278691070722, which contains 22 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (91288739) 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 15 ways as a sum of consecutive naturals, for example, 5864 + ... + 14729.

It is an arithmetic number, because the mean of its divisors is an integer number (6919584).

Almost surely, 2^91288769 is an apocalyptic number.

It is an amenable number.

91288769 is a deficient number, since it is larger than the sum of its proper divisors (19424575).

91288769 is a wasteful number, since it uses less digits than its factorization.

91288769 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 20648.

The product of its digits is 435456, while the sum is 50.

The square root of 91288769 is about 9554.5156339817. The cubic root of 91288769 is about 450.2694172672.

The spelling of 91288769 in words is "ninety-one million, two hundred eighty-eight thousand, seven hundred sixty-nine".