1123123213 has 2 divisors, whose sum is σ = 1123123214. Its totient is φ = 1123123212.

The previous prime is 1123123081. The next prime is 1123123217. The reversal of 1123123213 is 3123213211.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1074987369 + 48135844 = 32787^2 + 6938^2 .

It is an emirp because it is prime and its reverse (3123213211) is a distict prime.

It is a cyclic number.

It is not a de Polignac number, because 1123123213 - 2¹⁷ = 1122992141 is a prime.

It is a super-2 number, since 2×1123123213² = 2522811503158886738, which contains 22 as substring.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1123123217) 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, 561561606 + 561561607.

It is an arithmetic number, because the mean of its divisors is an integer number (561561607).

Almost surely, 2^1123123213 is an apocalyptic number.

It is an amenable number.

1123123213 is a deficient number, since it is larger than the sum of its proper divisors (1).

1123123213 is an equidigital number, since it uses as much as digits as its factorization.

1123123213 is an odious number, because the sum of its binary digits is odd.

The product of its digits is 216, while the sum is 19.

The square root of 1123123213 is about 33513.0304956147. The cubic root of 1123123213 is about 1039.4632378699.

Adding to 1123123213 its reverse (3123213211), we get a palindrome (4246336424).

The spelling of 1123123213 in words is "one billion, one hundred twenty-three million, one hundred twenty-three thousand, two hundred thirteen".