21203221233 has 4 divisors (see below), whose sum is σ = 28270961648. Its totient is φ = 14135480820.

The previous prime is 21203221231. The next prime is 21203221243. The reversal of 21203221233 is 33212230212.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4.

It is not a de Polignac number, because 21203221233 - 2¹ = 21203221231 is a prime.

It is a super-3 number, since 3×21203221233³ (a number of 32 digits) contains 333 as substring.

It is a Duffinian number.

It is not an unprimeable number, because it can be changed into a prime (21203221231) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 3533870203 + ... + 3533870208.

It is an arithmetic number, because the mean of its divisors is an integer number (7067740412).

Almost surely, 2^21203221233 is an apocalyptic number.

It is an amenable number.

21203221233 is a deficient number, since it is larger than the sum of its proper divisors (7067740415).

21203221233 is an equidigital number, since it uses as much as digits as its factorization.

21203221233 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 7067740414.

The product of its (nonzero) digits is 864, while the sum is 21.

Adding to 21203221233 its reverse (33212230212), we get a palindrome (54415451445).

The spelling of 21203221233 in words is "twenty-one billion, two hundred three million, two hundred twenty-one thousand, two hundred thirty-three".