1123123231 has 4 divisors (see below), whose sum is σ = 1182235000. Its totient is φ = 1064011464.

The previous prime is 1123123229. The next prime is 1123123237. The reversal of 1123123231 is 1323213211.

It is a semiprime because it is the product of two primes.

It is a cyclic number.

It is not a de Polignac number, because 1123123231 - 2¹ = 1123123229 is a prime.

It is a super-2 number, since 2×1123123231² = 2522811584023758722, which contains 22 as substring.

It is a Harshad number since it is a multiple of its sum of digits (19), and also a Moran number because the ratio is a prime number: 59111749 = 1123123231 / (1 + 1 + 2 + 3 + 1 + 2 + 3 + 2 + 3 + 1).

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1123123199 and 1123123208.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1123123237) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 29555856 + ... + 29555893.

It is an arithmetic number, because the mean of its divisors is an integer number (295558750).

Almost surely, 2^1123123231 is an apocalyptic number.

1123123231 is a deficient number, since it is larger than the sum of its proper divisors (59111769).

1123123231 is an equidigital number, since it uses as much as digits as its factorization.

1123123231 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 59111768.

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

The square root of 1123123231 is about 33513.0307641669. The cubic root of 1123123231 is about 1039.4632434230.

Adding to 1123123231 its reverse (1323213211), we get a palindrome (2446336442).

The spelling of 1123123231 in words is "one billion, one hundred twenty-three million, one hundred twenty-three thousand, two hundred thirty-one".