91109920 has 48 divisors (see below), whose sum is σ = 234819648. Its totient is φ = 33130240.

The previous prime is 91109917. The next prime is 91109933. The reversal of 91109920 is 2990119.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 24124 + ... + 27643.

It is an arithmetic number, because the mean of its divisors is an integer number (4892076).

Almost surely, 2^91109920 is an apocalyptic number.

It is an amenable number.

91109920 is an abundant number, since it is smaller than the sum of its proper divisors (143709728).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

91109920 is a wasteful number, since it uses less digits than its factorization.

91109920 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 51793 (or 51785 counting only the distinct ones).

The product of its (nonzero) digits is 1458, while the sum is 31.

The square root of 91109920 is about 9545.1516488739. The cubic root of 91109920 is about 449.9751755853.

It can be divided in two parts, 911099 and 20, that added together give a palindrome (911119).

The spelling of 91109920 in words is "ninety-one million, one hundred nine thousand, nine hundred twenty".