21210302333221 has 4 divisors (see below), whose sum is σ = 21266266192000. Its totient is φ = 21154338474444.

The previous prime is 21210302333179. The next prime is 21210302333347. The reversal of 21210302333221 is 12233320301212.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is a cyclic number.

It is not a de Polignac number, because 21210302333221 - 2¹⁷ = 21210302202149 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21210302330221) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 27981928821 + ... + 27981929578.

It is an arithmetic number, because the mean of its divisors is an integer number (5316566548000).

Almost surely, 2^{21210302333221} is an apocalyptic number.

It is an amenable number.

21210302333221 is a deficient number, since it is larger than the sum of its proper divisors (55963858779).

21210302333221 is an equidigital number, since it uses as much as digits as its factorization.

21210302333221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 55963858778.

The product of its (nonzero) digits is 2592, while the sum is 25.

Adding to 21210302333221 its reverse (12233320301212), we get a palindrome (33443622634433).

The spelling of 21210302333221 in words is "twenty-one trillion, two hundred ten billion, three hundred two million, three hundred thirty-three thousand, two hundred twenty-one".