11123320021 has 16 divisors (see below), whose sum is σ = 12229963776. Its totient is φ = 10032750000.

The previous prime is 11123319989. The next prime is 11123320037. The reversal of 11123320021 is 12002332111.

It is a cyclic number.

It is not a de Polignac number, because 11123320021 - 2⁵ = 11123319989 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 11123319977 and 11123320004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11123320051) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 1509496 + ... + 1516846.

It is an arithmetic number, because the mean of its divisors is an integer number (764372736).

Almost surely, 2^11123320021 is an apocalyptic number.

11123320021 is a gapful number since it is divisible by the number (11) formed by its first and last digit.

It is an amenable number.

11123320021 is a deficient number, since it is larger than the sum of its proper divisors (1106643755).

11123320021 is a wasteful number, since it uses less digits than its factorization.

11123320021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 8424.

The product of its (nonzero) digits is 72, while the sum is 16.

Adding to 11123320021 its reverse (12002332111), we get a palindrome (23125652132).

The spelling of 11123320021 in words is "eleven billion, one hundred twenty-three million, three hundred twenty thousand, twenty-one".