21031312023200 has 72 divisors (see below), whose sum is σ = 51351552469980. Its totient is φ = 8411072768000.

The previous prime is 21031312023199. The next prime is 21031312023209. The reversal of 21031312023200 is 232021313012.

It can be written as a sum of positive squares in 6 ways, for example, as 7232850844816 + 13798461178384 = 2689396^2 + 3714628^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (21031312023209) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 2374886 + ... + 6906714.

Almost surely, 2^{21031312023200} is an apocalyptic number.

21031312023200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21031312023200 is an abundant number, since it is smaller than the sum of its proper divisors (30320240446780).

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

21031312023200 is a wasteful number, since it uses less digits than its factorization.

21031312023200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4537650 (or 4537637 counting only the distinct ones).

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

Adding to 21031312023200 its reverse (232021313012), we get a palindrome (21263333336212).

The spelling of 21031312023200 in words is "twenty-one trillion, thirty-one billion, three hundred twelve million, twenty-three thousand, two hundred".