1111111111091 has 8 divisors (see below), whose sum is σ = 1176490499184. Its totient is φ = 1045733935360.

The previous prime is 1111111111087. The next prime is 1111111111093. The reversal of 1111111111091 is 1901111111111.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 1111111111091 - 2² = 1111111111087 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (1111111111093) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 542996 + ... + 1586526.

It is an arithmetic number, because the mean of its divisors is an integer number (147061312398).

Almost surely, 2^{1111111111091} is an apocalyptic number.

1111111111091 is a deficient number, since it is larger than the sum of its proper divisors (65379388093).

1111111111091 is a wasteful number, since it uses less digits than its factorization.

1111111111091 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1106181.

The product of its (nonzero) digits is 9, while the sum is 20.

Adding to 1111111111091 its sum of digits (20), we get a palindrome (1111111111111).

The spelling of 1111111111091 in words is "one trillion, one hundred eleven billion, one hundred eleven million, one hundred eleven thousand, ninety-one".