21013031200 has 72 divisors (see below), whose sum is σ = 58626372672. Its totient is φ = 7204465920.

The previous prime is 21013031161. The next prime is 21013031243. The reversal of 21013031200 is 213031012.

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 1870564 + ... + 1881763.

It is an arithmetic number, because the mean of its divisors is an integer number (814255176).

Almost surely, 2^21013031200 is an apocalyptic number.

21013031200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21013031200 is an abundant number, since it is smaller than the sum of its proper divisors (37613341472).

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

21013031200 is a wasteful number, since it uses less digits than its factorization.

21013031200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 3752354 (or 3752341 counting only the distinct ones).

The product of its (nonzero) digits is 36, while the sum is 13.

Adding to 21013031200 its reverse (213031012), we get a palindrome (21226062212).

The spelling of 21013031200 in words is "twenty-one billion, thirteen million, thirty-one thousand, two hundred".