21203333221 has 32 divisors (see below), whose sum is σ = 25306380288. Its totient is φ = 17383403520.

The previous prime is 21203333213. The next prime is 21203333231. The reversal of 21203333221 is 12233330212.

It is not a de Polignac number, because 21203333221 - 2³ = 21203333213 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 21203333192 and 21203333201.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21203333231) by changing a digit.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 10616595 + ... + 10618591.

It is an arithmetic number, because the mean of its divisors is an integer number (790824384).

Almost surely, 2^21203333221 is an apocalyptic number.

It is an amenable number.

21203333221 is a deficient number, since it is larger than the sum of its proper divisors (4103047067).

21203333221 is a wasteful number, since it uses less digits than its factorization.

21203333221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 2581.

The product of its (nonzero) digits is 1296, while the sum is 22.

Adding to 21203333221 its reverse (12233330212), we get a palindrome (33436663433).

The spelling of 21203333221 in words is "twenty-one billion, two hundred three million, three hundred thirty-three thousand, two hundred twenty-one".