2021222112521 has 2 divisors, whose sum is σ = 2021222112522. Its totient is φ = 2021222112520.

The previous prime is 2021222112493. The next prime is 2021222112523. The reversal of 2021222112521 is 1252112221202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1764816599296 + 256405513225 = 1328464^2 + 506365^2 .

It is a cyclic number.

It is not a de Polignac number, because 2021222112521 - 2³⁰ = 2020148370697 is a prime.

Together with 2021222112523, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (2021222112523) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1010611056260 + 1010611056261.

It is an arithmetic number, because the mean of its divisors is an integer number (1010611056261).

Almost surely, 2^{2021222112521} is an apocalyptic number.

It is an amenable number.

2021222112521 is a deficient number, since it is larger than the sum of its proper divisors (1).

2021222112521 is an equidigital number, since it uses as much as digits as its factorization.

2021222112521 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 640, while the sum is 23.

Adding to 2021222112521 its reverse (1252112221202), we get a palindrome (3273334333723).

The spelling of 2021222112521 in words is "two trillion, twenty-one billion, two hundred twenty-two million, one hundred twelve thousand, five hundred twenty-one".