1123231121 has 4 divisors (see below), whose sum is σ = 1150627044. Its totient is φ = 1095835200.

The previous prime is 1123231117. The next prime is 1123231129. The reversal of 1123231121 is 1211323211.

It is a semiprime because it is the product of two primes, and also an emirpimes, since its reverse is a distinct semiprime: 1211323211 = 7 ⋅173046173.

It can be written as a sum of positive squares in 2 ways, for example, as 592435600 + 530795521 = 24340^2 + 23039^2 .

It is a cyclic number.

It is not a de Polignac number, because 1123231121 - 2² = 1123231117 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 1123231121.

It is not an unprimeable number, because it can be changed into a prime (1123231129) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 13697900 + ... + 13697981.

It is an arithmetic number, because the mean of its divisors is an integer number (287656761).

Almost surely, 2^1123231121 is an apocalyptic number.

It is an amenable number.

1123231121 is a deficient number, since it is larger than the sum of its proper divisors (27395923).

1123231121 is an equidigital number, since it uses as much as digits as its factorization.

1123231121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 27395922.

The product of its digits is 72, while the sum is 17.

The square root of 1123231121 is about 33514.6403978918. The cubic root of 1123231121 is about 1039.4965268287.

Adding to 1123231121 its reverse (1211323211), we get a palindrome (2334554332).

The spelling of 1123231121 in words is "one billion, one hundred twenty-three million, two hundred thirty-one thousand, one hundred twenty-one".