11123311021 has 16 divisors (see below), whose sum is σ = 12383515440. Its totient is φ = 9942266880.

The previous prime is 11123311009. The next prime is 11123311039. The reversal of 11123311021 is 12011332111.

It is a happy number.

It can be written as a sum of positive squares in 8 ways, for example, as 82555396 + 11040755625 = 9086^2 + 105075^2 .

It is a cyclic number.

It is not a de Polignac number, because 11123311021 - 2⁷ = 11123310893 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11123310986 and 11123311004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11123311091) 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 15 ways as a sum of consecutive naturals, for example, 154866 + ... + 215011.

It is an arithmetic number, because the mean of its divisors is an integer number (773969715).

Almost surely, 2^11123311021 is an apocalyptic number.

It is an amenable number.

11123311021 is a deficient number, since it is larger than the sum of its proper divisors (1260204419).

11123311021 is a wasteful number, since it uses less digits than its factorization.

11123311021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 369984.

The product of its (nonzero) digits is 36, while the sum is 16.

Adding to 11123311021 its reverse (12011332111), we get a palindrome (23134643132).

It can be divided in two parts, 1112 and 3311021, that added together give a palindrome (3312133).

The spelling of 11123311021 in words is "eleven billion, one hundred twenty-three million, three hundred eleven thousand, twenty-one".