22221220220021 has 2 divisors, whose sum is σ = 22221220220022. Its totient is φ = 22221220220020.

The previous prime is 22221220220011. The next prime is 22221220220027. The reversal of 22221220220021 is 12002202212222.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21588382468900 + 632837751121 = 4646330^2 + 795511^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-22221220220021 is a prime.

It is a Sophie Germain prime.

It is a Curzon number.

It is a junction number, because it is equal to n+sod(n) for n = 22221220219975 and 22221220220002.

It is a congruent number.

It is not a weakly prime, because it can be changed into another prime (22221220220027) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 11110610110010 + 11110610110011.

It is an arithmetic number, because the mean of its divisors is an integer number (11110610110011).

Almost surely, 2^{22221220220021} is an apocalyptic number.

It is an amenable number.

22221220220021 is a deficient number, since it is larger than the sum of its proper divisors (1).

22221220220021 is an equidigital number, since it uses as much as digits as its factorization.

22221220220021 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 512, while the sum is 20.

Adding to 22221220220021 its reverse (12002202212222), we get a palindrome (34223422432243).

The spelling of 22221220220021 in words is "twenty-two trillion, two hundred twenty-one billion, two hundred twenty million, two hundred twenty thousand, twenty-one".