1131224021 has 2 divisors, whose sum is σ = 1131224022. Its totient is φ = 1131224020.

The previous prime is 1131224011. The next prime is 1131224023. The reversal of 1131224021 is 1204221311.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1122987121 + 8236900 = 33511^2 + 2870^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-1131224021 is a prime.

Together with 1131224023, it forms a pair of twin primes.

It is a Chen prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1131224023) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 565612010 + 565612011.

It is an arithmetic number, because the mean of its divisors is an integer number (565612011).

Almost surely, 2^1131224021 is an apocalyptic number.

It is an amenable number.

1131224021 is a deficient number, since it is larger than the sum of its proper divisors (1).

1131224021 is an equidigital number, since it uses as much as digits as its factorization.

1131224021 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 96, while the sum is 17.

The square root of 1131224021 is about 33633.6739146945. The cubic root of 1131224021 is about 1041.9563831100.

Adding to 1131224021 its reverse (1204221311), we get a palindrome (2335445332).

The spelling of 1131224021 in words is "one billion, one hundred thirty-one million, two hundred twenty-four thousand, twenty-one".