2121002212021 has 36 divisors (see below), whose sum is σ = 2720535581484. Its totient is φ = 1647513880320.

The previous prime is 2121002212009. The next prime is 2121002212037. The reversal of 2121002212021 is 1202122001212.

It is a happy number.

It can be written as a sum of positive squares in 2 ways, for example, as 800284111396 + 1320718100625 = 894586^2 + 1149225^2 .

It is not a de Polignac number, because 2121002212021 - 2¹⁵ = 2121002179253 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 2121002211986 and 2121002212004.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2121002210021) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 1315245 + ... + 2443741.

It is an arithmetic number, because the mean of its divisors is an integer number (75570432819).

Almost surely, 2^{2121002212021} is an apocalyptic number.

It is an amenable number.

2121002212021 is a deficient number, since it is larger than the sum of its proper divisors (599533369463).

2121002212021 is a wasteful number, since it uses less digits than its factorization.

2121002212021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1128850 (or 1128832 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 2121002212021 its reverse (1202122001212), we get a palindrome (3323124213233).

The spelling of 2121002212021 in words is "two trillion, one hundred twenty-one billion, two million, two hundred twelve thousand, twenty-one".