21031303321 has 4 divisors (see below), whose sum is σ = 24035775232. Its totient is φ = 18026831412.

The previous prime is 21031303273. The next prime is 21031303343. The reversal of 21031303321 is 12330313012.

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 21031303321 - 2¹⁵ = 21031270553 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21031303421) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 1502235945 + ... + 1502235958.

It is an arithmetic number, because the mean of its divisors is an integer number (6008943808).

Almost surely, 2^21031303321 is an apocalyptic number.

It is an amenable number.

21031303321 is a deficient number, since it is larger than the sum of its proper divisors (3004471911).

21031303321 is an equidigital number, since it uses as much as digits as its factorization.

21031303321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3004471910.

The product of its (nonzero) digits is 324, while the sum is 19.

Adding to 21031303321 its reverse (12330313012), we get a palindrome (33361616333).

The spelling of 21031303321 in words is "twenty-one billion, thirty-one million, three hundred three thousand, three hundred twenty-one".