1111111081 has 2 divisors, whose sum is σ = 1111111082. Its totient is φ = 1111111080.

The previous prime is 1111111037. The next prime is 1111111087. The reversal of 1111111081 is 1801111111.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 580039056 + 531072025 = 24084^2 + 23045^2 .

It is a cyclic number.

It is not a de Polignac number, because 1111111081 - 2¹⁷ = 1110980009 is a prime.

It is a super-3 number, since 3×1111111081³ (a number of 28 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 (1111111087) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 555555540 + 555555541.

It is an arithmetic number, because the mean of its divisors is an integer number (555555541).

Almost surely, 2^1111111081 is an apocalyptic number.

It is an amenable number.

1111111081 is a deficient number, since it is larger than the sum of its proper divisors (1).

1111111081 is an equidigital number, since it uses as much as digits as its factorization.

1111111081 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 16.

The square root of 1111111081 is about 33333.3328816667. The cubic root of 1111111081 is about 1035.7441592951.

Adding to 1111111081 its reverse (1801111111), we get a palindrome (2912222192).

The spelling of 1111111081 in words is "one billion, one hundred eleven million, one hundred eleven thousand, eighty-one".