1011111111121 has 2 divisors, whose sum is σ = 1011111111122. Its totient is φ = 1011111111120.

The previous prime is 1011111111083. The next prime is 1011111111137. The reversal of 1011111111121 is 1211111111101.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1005878614225 + 5232496896 = 1002935^2 + 72336^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1011111111121 is a prime.

It is not a weakly prime, because it can be changed into another prime (1011111111151) 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 as a sum of consecutive naturals, namely, 505555555560 + 505555555561.

It is an arithmetic number, because the mean of its divisors is an integer number (505555555561).

Almost surely, 2^{1011111111121} is an apocalyptic number.

It is an amenable number.

1011111111121 is a deficient number, since it is larger than the sum of its proper divisors (1).

1011111111121 is an equidigital number, since it uses as much as digits as its factorization.

1011111111121 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 2, while the sum is 13.

Adding to 1011111111121 its reverse (1211111111101), we get a palindrome (2222222222222).

The spelling of 1011111111121 in words is "one trillion, eleven billion, one hundred eleven million, one hundred eleven thousand, one hundred twenty-one".