11143121021 has 4 divisors (see below), whose sum is σ = 11444286492. Its totient is φ = 10841955552.

The previous prime is 11143120991. The next prime is 11143121063. The reversal of 11143121021 is 12012134111.

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

It can be written as a sum of positive squares in 2 ways, for example, as 6465928921 + 4677192100 = 80411^2 + 68390^2 .

It is a cyclic number.

It is not a de Polignac number, because 11143121021 - 2¹⁰ = 11143119997 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (11143121071) 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, 150582680 + ... + 150582753.

It is an arithmetic number, because the mean of its divisors is an integer number (2861071623).

Almost surely, 2^11143121021 is an apocalyptic number.

It is an amenable number.

11143121021 is a deficient number, since it is larger than the sum of its proper divisors (301165471).

11143121021 is an equidigital number, since it uses as much as digits as its factorization.

11143121021 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 301165470.

The product of its (nonzero) digits is 48, while the sum is 17.

Adding to 11143121021 its reverse (12012134111), we get a palindrome (23155255132).

The spelling of 11143121021 in words is "eleven billion, one hundred forty-three million, one hundred twenty-one thousand, twenty-one".