21203223312 has 20 divisors (see below), whose sum is σ = 54774993680. Its totient is φ = 7067741088.

The previous prime is 21203223289. The next prime is 21203223313. The reversal of 21203223312 is 21332230212.

It is a happy number.

It is not an unprimeable number, because it can be changed into a prime (21203223313) 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, 220866862 + ... + 220866957.

It is an arithmetic number, because the mean of its divisors is an integer number (2738749684).

Almost surely, 2^21203223312 is an apocalyptic number.

It is an amenable number.

21203223312 is an abundant number, since it is smaller than the sum of its proper divisors (33571770368).

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

21203223312 is a wasteful number, since it uses less digits than its factorization.

21203223312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 441733830 (or 441733824 counting only the distinct ones).

The product of its (nonzero) digits is 864, while the sum is 21.

Adding to 21203223312 its reverse (21332230212), we get a palindrome (42535453524).

The spelling of 21203223312 in words is "twenty-one billion, two hundred three million, two hundred twenty-three thousand, three hundred twelve".