1131442181 has 2 divisors, whose sum is σ = 1131442182. Its totient is φ = 1131442180.

The previous prime is 1131442177. The next prime is 1131442183. The reversal of 1131442181 is 1812441311.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 772339681 + 359102500 = 27791^2 + 18950^2 .

It is an emirp because it is prime and its reverse (1812441311) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1131442181 - 2² = 1131442177 is a prime.

It is a super-2 number, since 2×1131442181² = 2560322817892073522, which contains 22 as substring.

Together with 1131442183, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1131442181.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1131442183) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (11) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 565721090 + 565721091.

It is an arithmetic number, because the mean of its divisors is an integer number (565721091).

Almost surely, 2^1131442181 is an apocalyptic number.

It is an amenable number.

1131442181 is a deficient number, since it is larger than the sum of its proper divisors (1).

1131442181 is an equidigital number, since it uses as much as digits as its factorization.

1131442181 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 768, while the sum is 26.

The square root of 1131442181 is about 33636.9169366040. The cubic root of 1131442181 is about 1042.0233602926.

Adding to 1131442181 its reverse (1812441311), we get a palindrome (2943883492).

The spelling of 1131442181 in words is "one billion, one hundred thirty-one million, four hundred forty-two thousand, one hundred eighty-one".