21012320312 has 32 divisors (see below), whose sum is σ = 41119293600. Its totient is φ = 10047358464.

The previous prime is 21012320261. The next prime is 21012320317. The reversal of 21012320312 is 21302321012.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21012320317) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 1348148 + ... + 1363644.

It is an arithmetic number, because the mean of its divisors is an integer number (1284977925).

Almost surely, 2^21012320312 is an apocalyptic number.

It is an amenable number.

21012320312 is a deficient number, since it is larger than the sum of its proper divisors (20106973288).

21012320312 is a wasteful number, since it uses less digits than its factorization.

21012320312 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 22895 (or 22891 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 17.

Adding to 21012320312 its reverse (21302321012), we get a palindrome (42314641324).

The spelling of 21012320312 in words is "twenty-one billion, twelve million, three hundred twenty thousand, three hundred twelve".