2143105121 has 4 divisors (see below), whose sum is σ = 2143210500. Its totient is φ = 2142999744.

The previous prime is 2143105117. The next prime is 2143105199. The reversal of 2143105121 is 1215013412.

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 515789521 + 1627315600 = 22711^2 + 40340^2 .

It is a cyclic number.

It is not a de Polignac number, because 2143105121 - 2² = 2143105117 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2143105093 and 2143105102.

It is not an unprimeable number, because it can be changed into a prime (2143155121) 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, 11396 + ... + 66453.

It is an arithmetic number, because the mean of its divisors is an integer number (535802625).

Almost surely, 2^2143105121 is an apocalyptic number.

It is an amenable number.

2143105121 is a deficient number, since it is larger than the sum of its proper divisors (105379).

2143105121 is an equidigital number, since it uses as much as digits as its factorization.

2143105121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 105378.

The product of its (nonzero) digits is 240, while the sum is 20.

The square root of 2143105121 is about 46293.6833812130. The cubic root of 2143105121 is about 1289.2817187929.

Adding to 2143105121 its reverse (1215013412), we get a palindrome (3358118533).

The spelling of 2143105121 in words is "two billion, one hundred forty-three million, one hundred five thousand, one hundred twenty-one".