21131204244320 has 48 divisors (see below), whose sum is σ = 49923129534768. Its totient is φ = 8452370035200.

The previous prime is 21131204244289. The next prime is 21131204244373. The reversal of 21131204244320 is 2344240213112.

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, 11855447 + ... + 13520873.

It is an arithmetic number, because the mean of its divisors is an integer number (1040065198641).

Almost surely, 2^{21131204244320} is an apocalyptic number.

21131204244320 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21131204244320 is an abundant number, since it is smaller than the sum of its proper divisors (28791925290448).

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

21131204244320 is a wasteful number, since it uses less digits than its factorization.

21131204244320 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 1744743 (or 1744735 counting only the distinct ones).

The product of its (nonzero) digits is 9216, while the sum is 29.

Adding to 21131204244320 its reverse (2344240213112), we get a palindrome (23475444457432).

The spelling of 21131204244320 in words is "twenty-one trillion, one hundred thirty-one billion, two hundred four million, two hundred forty-four thousand, three hundred twenty".