91819100091 has 16 divisors (see below), whose sum is σ = 123840148608. Its totient is φ = 60509030400.

The previous prime is 91819100071. The next prime is 91819100119. The reversal of 91819100091 is 19000191819.

It is not a de Polignac number, because 91819100091 - 2⁹ = 91819099579 is a prime.

It is not an unprimeable number, because it can be changed into a prime (91819100071) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 353545 + ... + 555546.

It is an arithmetic number, because the mean of its divisors is an integer number (7740009288).

Almost surely, 2^91819100091 is an apocalyptic number.

91819100091 is a deficient number, since it is larger than the sum of its proper divisors (32021048517).

91819100091 is a wasteful number, since it uses less digits than its factorization.

91819100091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 909482.

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

The spelling of 91819100091 in words is "ninety-one billion, eight hundred nineteen million, one hundred thousand, ninety-one".