91009272820 has 24 divisors (see below), whose sum is σ = 191157884064. Its totient is φ = 36396392736.

The previous prime is 91009272817. The next prime is 91009272833. The reversal of 91009272820 is 2827290019.

It is a congruent number.

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, 354714 + ... + 554833.

It is an arithmetic number, because the mean of its divisors is an integer number (7964911836).

Almost surely, 2^91009272820 is an apocalyptic number.

It is an amenable number.

91009272820 is an abundant number, since it is smaller than the sum of its proper divisors (100148611244).

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

91009272820 is a wasteful number, since it uses less digits than its factorization.

91009272820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 914559 (or 914557 counting only the distinct ones).

The product of its (nonzero) digits is 36288, while the sum is 40.

The spelling of 91009272820 in words is "ninety-one billion, nine million, two hundred seventy-two thousand, eight hundred twenty".