20101010021221 has 2 divisors, whose sum is σ = 20101010021222. Its totient is φ = 20101010021220.

The previous prime is 20101010021203. The next prime is 20101010021231. The reversal of 20101010021221 is 12212001010102.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 19032619044321 + 1068390976900 = 4362639^2 + 1033630^2 .

It is a cyclic number.

It is not a de Polignac number, because 20101010021221 - 2¹⁷ = 20101009890149 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20101010021201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10050505010610 + 10050505010611.

It is an arithmetic number, because the mean of its divisors is an integer number (10050505010611).

Almost surely, 2^{20101010021221} is an apocalyptic number.

It is an amenable number.

20101010021221 is a deficient number, since it is larger than the sum of its proper divisors (1).

20101010021221 is an equidigital number, since it uses as much as digits as its factorization.

20101010021221 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 20101010021221 its reverse (12212001010102), we get a palindrome (32313011031323).

The spelling of 20101010021221 in words is "twenty trillion, one hundred one billion, ten million, twenty-one thousand, two hundred twenty-one".