91009191010 has 16 divisors (see below), whose sum is σ = 164721610872. Its totient is φ = 36202550400.

The previous prime is 91009190977. The next prime is 91009191017. The reversal of 91009191010 is 1019190019.

It can be written as a sum of positive squares in 4 ways, for example, as 60418131601 + 30591059409 = 245801^2 + 174903^2 .

It is not an unprimeable number, because it can be changed into a prime (91009191017) 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, 25138851 + ... + 25142470.

Almost surely, 2^91009191010 is an apocalyptic number.

91009191010 is a deficient number, since it is larger than the sum of its proper divisors (73712419862).

91009191010 is a wasteful number, since it uses less digits than its factorization.

91009191010 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 50281509.

The product of its (nonzero) digits is 729, while the sum is 31.

The spelling of 91009191010 in words is "ninety-one billion, nine million, one hundred ninety-one thousand, ten".