2130121120021 has 4 divisors (see below), whose sum is σ = 2165041138444. Its totient is φ = 2095201101600.

The previous prime is 2130121120013. The next prime is 2130121120063. The reversal of 2130121120021 is 1200211210312.

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 27693619396 + 2102427500625 = 166414^2 + 1449975^2 .

It is a cyclic number.

It is not a de Polignac number, because 2130121120021 - 2³ = 2130121120013 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 2130121119977 and 2130121120004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2130121123021) 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, 17460009120 + ... + 17460009241.

It is an arithmetic number, because the mean of its divisors is an integer number (541260284611).

Almost surely, 2^{2130121120021} is an apocalyptic number.

It is an amenable number.

2130121120021 is a deficient number, since it is larger than the sum of its proper divisors (34920018423).

2130121120021 is an equidigital number, since it uses as much as digits as its factorization.

2130121120021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 34920018422.

The product of its (nonzero) digits is 48, while the sum is 16.

Adding to 2130121120021 its reverse (1200211210312), we get a palindrome (3330332330333).

The spelling of 2130121120021 in words is "two trillion, one hundred thirty billion, one hundred twenty-one million, one hundred twenty thousand, twenty-one".