1021122021221 has 2 divisors, whose sum is σ = 1021122021222. Its totient is φ = 1021122021220.

The previous prime is 1021122021203. The next prime is 1021122021223. The reversal of 1021122021221 is 1221202211201.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 937384130596 + 83737890625 = 968186^2 + 289375^2 .

It is a cyclic number.

It is not a de Polignac number, because 1021122021221 - 2¹⁰ = 1021122020197 is a prime.

Together with 1021122021223, it forms a pair of twin primes.

It is a Chen prime.

It is a self number, because there is not a number n which added to its sum of digits gives 1021122021221.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (1021122021223) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 510561010610 + 510561010611.

It is an arithmetic number, because the mean of its divisors is an integer number (510561010611).

Almost surely, 2^{1021122021221} is an apocalyptic number.

It is an amenable number.

1021122021221 is a deficient number, since it is larger than the sum of its proper divisors (1).

1021122021221 is an equidigital number, since it uses as much as digits as its factorization.

1021122021221 is an evil number, because the sum of its binary digits is even.

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

Adding to 1021122021221 its reverse (1221202211201), we get a palindrome (2242324232422).

The spelling of 1021122021221 in words is "one trillion, twenty-one billion, one hundred twenty-two million, twenty-one thousand, two hundred twenty-one".