2021011001221 has 2 divisors, whose sum is σ = 2021011001222. Its totient is φ = 2021011001220.

The previous prime is 2021011001203. The next prime is 2021011001231. The reversal of 2021011001221 is 1221001101202.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1926294168100 + 94716833121 = 1387910^2 + 307761^2 .

It is a cyclic number.

It is not a de Polignac number, because 2021011001221 - 2⁵ = 2021011001189 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2021011001201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1010505500610 + 1010505500611.

It is an arithmetic number, because the mean of its divisors is an integer number (1010505500611).

Almost surely, 2^{2021011001221} is an apocalyptic number.

It is an amenable number.

2021011001221 is a deficient number, since it is larger than the sum of its proper divisors (1).

2021011001221 is an equidigital number, since it uses as much as digits as its factorization.

2021011001221 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 16, while the sum is 13.

Adding to 2021011001221 its reverse (1221001101202), we get a palindrome (3242012102423).

The spelling of 2021011001221 in words is "two trillion, twenty-one billion, eleven million, one thousand, two hundred twenty-one".