2011231181 has 2 divisors, whose sum is σ = 2011231182. Its totient is φ = 2011231180.

The previous prime is 2011231177. The next prime is 2011231199. The reversal of 2011231181 is 1811321102.

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., 1021122025 + 990109156 = 31955^2 + 31466^2 .

It is a cyclic number.

It is not a de Polignac number, because 2011231181 - 2² = 2011231177 is a prime.

It is a super-2 number, since 2×2011231181² = 8090101726853309522, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2011231381) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1005615590 + 1005615591.

It is an arithmetic number, because the mean of its divisors is an integer number (1005615591).

Almost surely, 2^2011231181 is an apocalyptic number.

It is an amenable number.

2011231181 is a deficient number, since it is larger than the sum of its proper divisors (1).

2011231181 is an equidigital number, since it uses as much as digits as its factorization.

2011231181 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 96, while the sum is 20.

The square root of 2011231181 is about 44846.7521789483. The cubic root of 2011231181 is about 1262.2750492390.

Adding to 2011231181 its reverse (1811321102), we get a palindrome (3822552283).

The spelling of 2011231181 in words is "two billion, eleven million, two hundred thirty-one thousand, one hundred eighty-one".