20021144033221 has 2 divisors, whose sum is σ = 20021144033222. Its totient is φ = 20021144033220.

The previous prime is 20021144033213. The next prime is 20021144033237. The reversal of 20021144033221 is 12233044112002.

It is a weak prime.

It can be written as a sum of positive squares in only one way, i.e., 13140726500196 + 6880417533025 = 3625014^2 + 2623055^2 .

It is a cyclic number.

It is not a de Polignac number, because 20021144033221 - 2³ = 20021144033213 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (20021144033201) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10010572016610 + 10010572016611.

It is an arithmetic number, because the mean of its divisors is an integer number (10010572016611).

Almost surely, 2^{20021144033221} is an apocalyptic number.

It is an amenable number.

20021144033221 is a deficient number, since it is larger than the sum of its proper divisors (1).

20021144033221 is an equidigital number, since it uses as much as digits as its factorization.

20021144033221 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 2304, while the sum is 25.

Adding to 20021144033221 its reverse (12233044112002), we get a palindrome (32254188145223).

The spelling of 20021144033221 in words is "twenty trillion, twenty-one billion, one hundred forty-four million, thirty-three thousand, two hundred twenty-one".