12111001081 has 2 divisors, whose sum is σ = 12111001082. Its totient is φ = 12111001080.

The previous prime is 12111001073. The next prime is 12111001099. The reversal of 12111001081 is 18010011121.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 7729223056 + 4381778025 = 87916^2 + 66195^2 .

It is a cyclic number.

It is not a de Polignac number, because 12111001081 - 2³ = 12111001073 is a prime.

It is a super-2 number, since 2×12111001081² (a number of 21 digits) contains 22 as substring.

It is not a weakly prime, because it can be changed into another prime (12111001181) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 6055500540 + 6055500541.

It is an arithmetic number, because the mean of its divisors is an integer number (6055500541).

Almost surely, 2^12111001081 is an apocalyptic number.

It is an amenable number.

12111001081 is a deficient number, since it is larger than the sum of its proper divisors (1).

12111001081 is an equidigital number, since it uses as much as digits as its factorization.

12111001081 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 16, while the sum is 16.

The spelling of 12111001081 in words is "twelve billion, one hundred eleven million, one thousand, eighty-one".