21322553321 has 2 divisors, whose sum is σ = 21322553322. Its totient is φ = 21322553320.

The previous prime is 21322553303. The next prime is 21322553323. The reversal of 21322553321 is 12335522312.

It is a strong prime.

It can be written as a sum of positive squares in only one way, i.e., 21251808400 + 70744921 = 145780^2 + 8411^2 .

It is a cyclic number.

It is not a de Polignac number, because 21322553321 - 2³⁰ = 20248811497 is a prime.

Together with 21322553323, it forms a pair of twin primes.

It is a Chen prime.

It is not a weakly prime, because it can be changed into another prime (21322553323) by changing a digit.

It is a polite number, since it can be written as a sum of consecutive naturals, namely, 10661276660 + 10661276661.

It is an arithmetic number, because the mean of its divisors is an integer number (10661276661).

Almost surely, 2^21322553321 is an apocalyptic number.

It is an amenable number.

21322553321 is a deficient number, since it is larger than the sum of its proper divisors (1).

21322553321 is an equidigital number, since it uses as much as digits as its factorization.

21322553321 is an evil number, because the sum of its binary digits is even.

The product of its digits is 10800, while the sum is 29.

The spelling of 21322553321 in words is "twenty-one billion, three hundred twenty-two million, five hundred fifty-three thousand, three hundred twenty-one".