21312223232 has 48 divisors (see below), whose sum is σ = 43988817600. Its totient is φ = 10312335360.

The previous prime is 21312223217. The next prime is 21312223277. The reversal of 21312223232 is 23232221312.

It is a junction number, because it is equal to n+sod(n) for n = 21312223198 and 21312223207.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 104357 + ... + 231332.

It is an arithmetic number, because the mean of its divisors is an integer number (916433700).

Almost surely, 2^21312223232 is an apocalyptic number.

It is an amenable number.

21312223232 is an abundant number, since it is smaller than the sum of its proper divisors (22676594368).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21312223232 is an equidigital number, since it uses as much as digits as its factorization.

21312223232 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 335742 (or 335722 counting only the distinct ones).

The product of its digits is 1728, while the sum is 23.

Adding to 21312223232 its reverse (23232221312), we get a palindrome (44544444544).

The spelling of 21312223232 in words is "twenty-one billion, three hundred twelve million, two hundred twenty-three thousand, two hundred thirty-two".