2121440121 has 24 divisors (see below), whose sum is σ = 3200857920. Its totient is φ = 1351395936.

The previous prime is 2121440099. The next prime is 2121440137. The reversal of 2121440121 is 1210441212.

2121440121 is a `hidden beast` number, since 212 + 1 + 440 + 12 + 1 = 666.

It is not a de Polignac number, because 2121440121 - 2¹⁹ = 2120915833 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2121440094 and 2121440103.

It is not an unprimeable number, because it can be changed into a prime (2121440921) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 216490 + ... + 226076.

It is an arithmetic number, because the mean of its divisors is an integer number (133369080).

Almost surely, 2^2121440121 is an apocalyptic number.

It is an amenable number.

2121440121 is a deficient number, since it is larger than the sum of its proper divisors (1079417799).

2121440121 is a wasteful number, since it uses less digits than its factorization.

2121440121 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 10685 (or 10682 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 18.

The square root of 2121440121 is about 46059.0937926486. The cubic root of 2121440121 is about 1284.9224763094.

Adding to 2121440121 its reverse (1210441212), we get a palindrome (3331881333).

The spelling of 2121440121 in words is "two billion, one hundred twenty-one million, four hundred forty thousand, one hundred twenty-one".