2120121121021 has 4 divisors (see below), whose sum is σ = 2231706443200. Its totient is φ = 2008535798844.

The previous prime is 2120121120977. The next prime is 2120121121039. The reversal of 2120121121021 is 1201211210212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 2120121121021 - 2¹⁹ = 2120120596733 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2120121120986 and 2120121121004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2120121121121) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 55792661061 + ... + 55792661098.

It is an arithmetic number, because the mean of its divisors is an integer number (557926610800).

Almost surely, 2^{2120121121021} is an apocalyptic number.

It is an amenable number.

2120121121021 is a deficient number, since it is larger than the sum of its proper divisors (111585322179).

2120121121021 is a wasteful number, since it uses less digits than its factorization.

2120121121021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 111585322178.

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 2120121121021 its reverse (1201211210212), we get a palindrome (3321332331233).

It can be divided in two parts, 2 and 120121121021, that multiplied together give a palindrome (240242242042).

The spelling of 2120121121021 in words is "two trillion, one hundred twenty billion, one hundred twenty-one million, one hundred twenty-one thousand, twenty-one".