2021011212221 has 4 divisors (see below), whose sum is σ = 2049476158944. Its totient is φ = 1992546265500.

The previous prime is 2021011212203. The next prime is 2021011212223. The reversal of 2021011212221 is 1222121101202.

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 2021011212221 - 2¹⁴ = 2021011195837 is a prime.

It is a Duffinian number.

It is a self number, because there is not a number n which added to its sum of digits gives 2021011212221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2021011212223) 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, 14232473255 + ... + 14232473396.

It is an arithmetic number, because the mean of its divisors is an integer number (512369039736).

Almost surely, 2^{2021011212221} is an apocalyptic number.

It is an amenable number.

2021011212221 is a deficient number, since it is larger than the sum of its proper divisors (28464946723).

2021011212221 is an equidigital number, since it uses as much as digits as its factorization.

2021011212221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 28464946722.

The product of its (nonzero) digits is 64, while the sum is 17.

Adding to 2021011212221 its reverse (1222121101202), we get a palindrome (3243132313423).

The spelling of 2021011212221 in words is "two trillion, twenty-one billion, eleven million, two hundred twelve thousand, two hundred twenty-one".