21310303221 has 24 divisors (see below), whose sum is σ = 31786428960. Its totient is φ = 13749142176.

The previous prime is 21310303219. The next prime is 21310303253. The reversal of 21310303221 is 12230301312.

21310303221 is a `hidden beast` number, since 2 + 1 + 310 + 30 + 322 + 1 = 666.

It is not a de Polignac number, because 21310303221 - 2¹ = 21310303219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21310303194 and 21310303203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21310303121) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 210411 + ... + 294776.

It is an arithmetic number, because the mean of its divisors is an integer number (1324434540).

Almost surely, 2^21310303221 is an apocalyptic number.

It is an amenable number.

21310303221 is a deficient number, since it is larger than the sum of its proper divisors (10476125739).

21310303221 is a wasteful number, since it uses less digits than its factorization.

21310303221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 505345 (or 505342 counting only the distinct ones).

The product of its (nonzero) digits is 216, while the sum is 18.

Adding to 21310303221 its reverse (12230301312), we get a palindrome (33540604533).

The spelling of 21310303221 in words is "twenty-one billion, three hundred ten million, three hundred three thousand, two hundred twenty-one".