11011111121161 has 2 divisors, whose sum is σ = 11011111121162. Its totient is φ = 11011111121160.

The previous prime is 11011111121141. The next prime is 11011111121189. The reversal of 11011111121161 is 16112111111011.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 8419027221136 + 2592083900025 = 2901556^2 + 1609995^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11011111121161 is a prime.

It is not a weakly prime, because it can be changed into another prime (11011111121141) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5505555560580 + 5505555560581.

It is an arithmetic number, because the mean of its divisors is an integer number (5505555560581).

Almost surely, 2^{11011111121161} is an apocalyptic number.

It is an amenable number.

11011111121161 is a deficient number, since it is larger than the sum of its proper divisors (1).

11011111121161 is an equidigital number, since it uses as much as digits as its factorization.

11011111121161 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 12, while the sum is 19.

Adding to 11011111121161 its reverse (16112111111011), we get a palindrome (27123222232172).

The spelling of 11011111121161 in words is "eleven trillion, eleven billion, one hundred eleven million, one hundred twenty-one thousand, one hundred sixty-one".