2121001243 has 16 divisors (see below), whose sum is σ = 2295216000. Its totient is φ = 1952750592.

The previous prime is 2121001241. The next prime is 2121001261. The reversal of 2121001243 is 3421001212.

It is a cyclic number.

It is not a de Polignac number, because 2121001243 - 2¹ = 2121001241 is a prime.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (2121001241) 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, 139143 + ... + 153631.

It is an arithmetic number, because the mean of its divisors is an integer number (143451000).

Almost surely, 2^2121001243 is an apocalyptic number.

2121001243 is a deficient number, since it is larger than the sum of its proper divisors (174214757).

2121001243 is a wasteful number, since it uses less digits than its factorization.

2121001243 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 14694.

The product of its (nonzero) digits is 96, while the sum is 16.

The square root of 2121001243 is about 46054.3292536109. The cubic root of 2121001243 is about 1284.8338630614.

Adding to 2121001243 its reverse (3421001212), we get a palindrome (5542002455).

The spelling of 2121001243 in words is "two billion, one hundred twenty-one million, one thousand, two hundred forty-three".