1001111111091 has 48 divisors (see below), whose sum is σ = 1779887089344. Its totient is φ = 528018849792.

The previous prime is 1001111111089. The next prime is 1001111111107. The reversal of 1001111111091 is 1901111111001.

It is not a de Polignac number, because 1001111111091 - 2¹ = 1001111111089 is a prime.

It is not an unprimeable number, because it can be changed into a prime (1001111111491) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 13145475 + ... + 13221411.

It is an arithmetic number, because the mean of its divisors is an integer number (37080981028).

Almost surely, 2^{1001111111091} is an apocalyptic number.

1001111111091 is a deficient number, since it is larger than the sum of its proper divisors (778775978253).

1001111111091 is a wasteful number, since it uses less digits than its factorization.

1001111111091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 92060 (or 92057 counting only the distinct ones).

The product of its (nonzero) digits is 9, while the sum is 18.

Adding to 1001111111091 its reverse (1901111111001), we get a palindrome (2902222222092).

The spelling of 1001111111091 in words is "one trillion, one billion, one hundred eleven million, one hundred eleven thousand, ninety-one".