91119891 has 8 divisors (see below), whose sum is σ = 122858640. Its totient is φ = 60063872.

The previous prime is 91119869. The next prime is 91119929. The reversal of 91119891 is 19891119.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 91119891 - 2¹¹ = 91117843 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91119811) 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 7 ways as a sum of consecutive naturals, for example, 170370 + ... + 170903.

It is an arithmetic number, because the mean of its divisors is an integer number (15357330).

Almost surely, 2^91119891 is an apocalyptic number.

91119891 is a deficient number, since it is larger than the sum of its proper divisors (31738749).

91119891 is a wasteful number, since it uses less digits than its factorization.

91119891 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 341365.

The product of its digits is 5832, while the sum is 39.

The square root of 91119891 is about 9545.6739416345. The cubic root of 91119891 is about 449.9915899663.

It can be divided in two parts, 911 and 19891, that added together give a palindrome (20802).

The spelling of 91119891 in words is "ninety-one million, one hundred nineteen thousand, eight hundred ninety-one".