31330332221 has 4 divisors (see below), whose sum is σ = 31330986972. Its totient is φ = 31329677472.

The previous prime is 31330332199. The next prime is 31330332239. The reversal of 31330332221 is 12223303313.

It is a semiprime because it is the product of two primes.

It can be written as a sum of positive squares in 2 ways, for example, as 18193963225 + 13136368996 = 134885^2 + 114614^2 .

It is a cyclic number.

It is not a de Polignac number, because 31330332221 - 2¹⁸ = 31330070077 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 (31330332251) 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 in 3 ways as a sum of consecutive naturals, for example, 249410 + ... + 353363.

It is an arithmetic number, because the mean of its divisors is an integer number (7832746743).

Almost surely, 2^31330332221 is an apocalyptic number.

It is an amenable number.

31330332221 is a deficient number, since it is larger than the sum of its proper divisors (654751).

31330332221 is an equidigital number, since it uses as much as digits as its factorization.

31330332221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 654750.

The product of its (nonzero) digits is 1944, while the sum is 23.

Adding to 31330332221 its reverse (12223303313), we get a palindrome (43553635534).

The spelling of 31330332221 in words is "thirty-one billion, three hundred thirty million, three hundred thirty-two thousand, two hundred twenty-one".