21202030321 has 2 divisors, whose sum is σ = 21202030322. Its totient is φ = 21202030320.

The previous prime is 21202030277. The next prime is 21202030337. The reversal of 21202030321 is 12303020212.

It is an a-pointer prime, because the next prime (21202030337) can be obtained adding 21202030321 to its sum of digits (16).

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 18614782096 + 2587248225 = 136436^2 + 50865^2 .

It is a cyclic number.

It is not a de Polignac number, because 21202030321 - 2⁷ = 21202030193 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21202030295 and 21202030304.

It is not a weakly prime, because it can be changed into another prime (21202036321) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (23) of ones.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10601015160 + 10601015161.

It is an arithmetic number, because the mean of its divisors is an integer number (10601015161).

Almost surely, 2^21202030321 is an apocalyptic number.

It is an amenable number.

21202030321 is a deficient number, since it is larger than the sum of its proper divisors (1).

21202030321 is an equidigital number, since it uses as much as digits as its factorization.

21202030321 is an odious number, because the sum of its binary digits is odd.

The product of its (nonzero) digits is 144, while the sum is 16.

Adding to 21202030321 its reverse (12303020212), we get a palindrome (33505050533).

The spelling of 21202030321 in words is "twenty-one billion, two hundred two million, thirty thousand, three hundred twenty-one".