21200021321 has 8 divisors (see below), whose sum is σ = 21429663360. Its totient is φ = 20971481328.

The previous prime is 21200021317. The next prime is 21200021369. The reversal of 21200021321 is 12312000212.

It is a happy number.

It is a sphenic number, since it is the product of 3 distinct primes.

It is a cyclic number.

It is not a de Polignac number, because 21200021321 - 2² = 21200021317 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21200021296 and 21200021305.

It is not an unprimeable number, because it can be changed into a prime (21200021371) by changing a digit.

It is a polite number, since it can be written in 7 ways as a sum of consecutive naturals, for example, 236801 + ... + 313806.

It is an arithmetic number, because the mean of its divisors is an integer number (2678707920).

Almost surely, 2^21200021321 is an apocalyptic number.

It is an amenable number.

21200021321 is a deficient number, since it is larger than the sum of its proper divisors (229642039).

21200021321 is a wasteful number, since it uses less digits than its factorization.

21200021321 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 551023.

The product of its (nonzero) digits is 48, while the sum is 14.

Adding to 21200021321 its reverse (12312000212), we get a palindrome (33512021533).

The spelling of 21200021321 in words is "twenty-one billion, two hundred million, twenty-one thousand, three hundred twenty-one".