21200031321 has 16 divisors (see below), whose sum is σ = 32336176128. Its totient is φ = 12102541200.

The previous prime is 21200031301. The next prime is 21200031343. The reversal of 21200031321 is 12313000212.

It is not a de Polignac number, because 21200031321 - 2⁵ = 21200031289 is a prime.

It is a super-2 number, since 2×21200031321² (a number of 21 digits) contains 22 as substring.

It is a self number, because there is not a number n which added to its sum of digits gives 21200031321.

It is not an unprimeable number, because it can be changed into a prime (21200031301) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 467935 + ... + 511236.

It is an arithmetic number, because the mean of its divisors is an integer number (2021011008).

Almost surely, 2^21200031321 is an apocalyptic number.

21200031321 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21200031321 is a deficient number, since it is larger than the sum of its proper divisors (11136144807).

21200031321 is a wasteful number, since it uses less digits than its factorization.

21200031321 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 980212.

The product of its (nonzero) digits is 72, while the sum is 15.

Adding to 21200031321 its reverse (12313000212), we get a palindrome (33513031533).

The spelling of 21200031321 in words is "twenty-one billion, two hundred million, thirty-one thousand, three hundred twenty-one".