1123111021 has 4 divisors (see below), whose sum is σ = 1123187292. Its totient is φ = 1123034752.

The previous prime is 1123111009. The next prime is 1123111051. The reversal of 1123111021 is 1201113211.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a brilliant number, because the two primes have the same length.

It can be written as a sum of positive squares in 2 ways, for example, as 85562500 + 1037548521 = 9250^2 + 32211^2 .

It is a cyclic number.

It is not a de Polignac number, because 1123111021 - 2¹³ = 1123102829 is a prime.

It is a super-2 number, since 2×1123111021² = 2522756730983324882, which contains 22 as substring.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 1123110992 and 1123111010.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (1123111051) 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, 8230 + ... + 48103.

It is an arithmetic number, because the mean of its divisors is an integer number (280796823).

Almost surely, 2^1123111021 is an apocalyptic number.

It is an amenable number.

1123111021 is a deficient number, since it is larger than the sum of its proper divisors (76271).

1123111021 is an equidigital number, since it uses as much as digits as its factorization.

1123111021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 76270.

The product of its (nonzero) digits is 12, while the sum is 13.

The square root of 1123111021 is about 33512.8485957252. The cubic root of 1123111021 is about 1039.4594765783.

Adding to 1123111021 its reverse (1201113211), we get a palindrome (2324224232).

The spelling of 1123111021 in words is "one billion, one hundred twenty-three million, one hundred eleven thousand, twenty-one".