21040222321 has 2 divisors, whose sum is σ = 21040222322. Its totient is φ = 21040222320.

The previous prime is 21040222271. The next prime is 21040222339. The reversal of 21040222321 is 12322204012.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18888654096 + 2151568225 = 137436^2 + 46385^2 .

It is a cyclic number.

It is not a de Polignac number, because 21040222321 - 2¹⁷ = 21040091249 is a prime.

It is not a weakly prime, because it can be changed into another prime (21040222351) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10520111160 + 10520111161.

It is an arithmetic number, because the mean of its divisors is an integer number (10520111161).

Almost surely, 2^21040222321 is an apocalyptic number.

It is an amenable number.

21040222321 is a deficient number, since it is larger than the sum of its proper divisors (1).

21040222321 is an equidigital number, since it uses as much as digits as its factorization.

21040222321 is an evil number, because the sum of its binary digits is even.

The product of its (nonzero) digits is 384, while the sum is 19.

Adding to 21040222321 its reverse (12322204012), we get a palindrome (33362426333).

The spelling of 21040222321 in words is "twenty-one billion, forty million, two hundred twenty-two thousand, three hundred twenty-one".