91000010020 has 48 divisors (see below), whose sum is σ = 198517132800. Its totient is φ = 34997728640.

The previous prime is 91000010011. The next prime is 91000010033. The reversal of 91000010020 is 2001000019.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 189616 + ... + 466855.

It is an arithmetic number, because the mean of its divisors is an integer number (4135773600).

Almost surely, 2^91000010020 is an apocalyptic number.

It is an amenable number.

91000010020 is an abundant number, since it is smaller than the sum of its proper divisors (107517122780).

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

91000010020 is a wasteful number, since it uses less digits than its factorization.

91000010020 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 656748 (or 656746 counting only the distinct ones).

The product of its (nonzero) digits is 18, while the sum is 13.

Adding to 91000010020 its reverse (2001000019), we get a palindrome (93001010039).

The spelling of 91000010020 in words is "ninety-one billion, ten thousand, twenty".