21203213312 has 88 divisors (see below), whose sum is σ = 43509328896. Its totient is φ = 10322178048.

The previous prime is 21203213261. The next prime is 21203213333. The reversal of 21203213312 is 21331230212.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 19505633 + ... + 19506719.

It is an arithmetic number, because the mean of its divisors is an integer number (494424192).

Almost surely, 2^21203213312 is an apocalyptic number.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21203213312, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (21754664448).

21203213312 is an abundant number, since it is smaller than the sum of its proper divisors (22306115584).

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

21203213312 is a wasteful number, since it uses less digits than its factorization.

21203213312 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1593 (or 1575 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 20.

Adding to 21203213312 its reverse (21331230212), we get a palindrome (42534443524).

The spelling of 21203213312 in words is "twenty-one billion, two hundred three million, two hundred thirteen thousand, three hundred twelve".