91111111010 has 32 divisors (see below), whose sum is σ = 164299430592. Its totient is φ = 36377965120.

The previous prime is 91111111009. The next prime is 91111111067. The reversal of 91111111010 is 1011111119.

It is a self number, because there is not a number n which added to its sum of digits gives 91111111010.

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, 22269065 + ... + 22273155.

It is an arithmetic number, because the mean of its divisors is an integer number (5134357206).

Almost surely, 2^91111111010 is an apocalyptic number.

91111111010 is a deficient number, since it is larger than the sum of its proper divisors (73188319582).

91111111010 is a wasteful number, since it uses less digits than its factorization.

91111111010 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7618.

The product of its (nonzero) digits is 9, while the sum is 17.

Adding to 91111111010 its reverse (1011111119), we get a palindrome (92122222129).

The spelling of 91111111010 in words is "ninety-one billion, one hundred eleven million, one hundred eleven thousand, ten".