2221221200021 has 2 divisors, whose sum is σ = 2221221200022. Its totient is φ = 2221221200020.

The previous prime is 2221221199973. The next prime is 2221221200041. The reversal of 2221221200021 is 1200021221222.

It is a happy number.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 1780476579025 + 440744620996 = 1334345^2 + 663886^2 .

It is a cyclic number.

It is not a de Polignac number, because 2221221200021 - 2¹⁴ = 2221221183637 is a prime.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (2221221200041) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 1110610600010 + 1110610600011.

It is an arithmetic number, because the mean of its divisors is an integer number (1110610600011).

Almost surely, 2^{2221221200021} is an apocalyptic number.

It is an amenable number.

2221221200021 is a deficient number, since it is larger than the sum of its proper divisors (1).

2221221200021 is an equidigital number, since it uses as much as digits as its factorization.

2221221200021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 128, while the sum is 17.

Adding to 2221221200021 its reverse (1200021221222), we get a palindrome (3421242421243).

It can be divided in two parts, 2221221 and 200021, that added together give a palindrome (2421242).

The spelling of 2221221200021 in words is "two trillion, two hundred twenty-one billion, two hundred twenty-one million, two hundred thousand, twenty-one".