11111000081 has 2 divisors, whose sum is σ = 11111000082. Its totient is φ = 11111000080.

The previous prime is 11111000071. The next prime is 11111000119. The reversal of 11111000081 is 18000011111.

It is a happy number.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 11033401600 + 77598481 = 105040^2 + 8809^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-11111000081 is a prime.

It is a super-2 number, since 2×11111000081² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (11111000051) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 5555500040 + 5555500041.

It is an arithmetic number, because the mean of its divisors is an integer number (5555500041).

Almost surely, 2^11111000081 is an apocalyptic number.

It is an amenable number.

11111000081 is a deficient number, since it is larger than the sum of its proper divisors (1).

11111000081 is an equidigital number, since it uses as much as digits as its factorization.

11111000081 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 14.

Adding to 11111000081 its reverse (18000011111), we get a palindrome (29111011192).

The spelling of 11111000081 in words is "eleven billion, one hundred eleven million, eighty-one", and thus it is an aban number.