11111111011081 has 2 divisors, whose sum is σ = 11111111011082. Its totient is φ = 11111111011080.

The previous prime is 11111111011037. The next prime is 11111111011153. The reversal of 11111111011081 is 18011011111111.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 10950698745856 + 160412265225 = 3309184^2 + 400515^2 .

It is a cyclic number.

It is not a de Polignac number, because 11111111011081 - 2²⁵ = 11111077456649 is a prime.

It is a super-3 number, since 3×11111111011081³ (a number of 40 digits) contains 333 as substring. Note that it is a super-d number also for d = 2.

It is not a weakly prime, because it can be changed into another prime (11111111011981) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5555555505540 + 5555555505541.

It is an arithmetic number, because the mean of its divisors is an integer number (5555555505541).

Almost surely, 2^{11111111011081} is an apocalyptic number.

It is an amenable number.

11111111011081 is a deficient number, since it is larger than the sum of its proper divisors (1).

11111111011081 is an equidigital number, since it uses as much as digits as its factorization.

11111111011081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 8, while the sum is 19.

Adding to 11111111011081 its reverse (18011011111111), we get a palindrome (29122122122192).

The spelling of 11111111011081 in words is "eleven trillion, one hundred eleven billion, one hundred eleven million, eleven thousand, eighty-one".