1011111121191 has 4 divisors (see below), whose sum is σ = 1348148161592. Its totient is φ = 674074080792.

The previous prime is 1011111121187. The next prime is 1011111121253. The reversal of 1011111121191 is 1911211111101.

It is a semiprime because it is the product of two primes.

It is not a de Polignac number, because 1011111121191 - 2² = 1011111121187 is a prime.

It is a super-2 number, since 2×1011111121191² (a number of 25 digits) contains 22 as substring.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1011111120191) 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 3 ways as a sum of consecutive naturals, for example, 168518520196 + ... + 168518520201.

It is an arithmetic number, because the mean of its divisors is an integer number (337037040398).

Almost surely, 2^{1011111121191} is an apocalyptic number.

1011111121191 is a deficient number, since it is larger than the sum of its proper divisors (337037040401).

1011111121191 is an equidigital number, since it uses as much as digits as its factorization.

1011111121191 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 337037040400.

The product of its (nonzero) digits is 18, while the sum is 21.

Adding to 1011111121191 its reverse (1911211111101), we get a palindrome (2922322232292).

The spelling of 1011111121191 in words is "one trillion, eleven billion, one hundred eleven million, one hundred twenty-one thousand, one hundred ninety-one".