21001332233 has 6 divisors (see below), whose sum is σ = 24430121226. Its totient is φ = 18001141872.

The previous prime is 21001332221. The next prime is 21001332239. The reversal of 21001332233 is 33223310012.

It can be written as a sum of positive squares in only one way, i.e., 18854585344 + 2146746889 = 137312^2 + 46333^2 .

It is not a de Polignac number, because 21001332233 - 2¹⁰ = 21001331209 is a prime.

It is not an unprimeable number, because it can be changed into a prime (21001332239) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 5 ways as a sum of consecutive naturals, for example, 214299260 + ... + 214299357.

It is an arithmetic number, because the mean of its divisors is an integer number (4071686871).

Almost surely, 2^21001332233 is an apocalyptic number.

It is an amenable number.

21001332233 is a deficient number, since it is larger than the sum of its proper divisors (3428788993).

21001332233 is an equidigital number, since it uses as much as digits as its factorization.

21001332233 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 428598631 (or 428598624 counting only the distinct ones).

The product of its (nonzero) digits is 648, while the sum is 20.

Adding to 21001332233 its reverse (33223310012), we get a palindrome (54224642245).

The spelling of 21001332233 in words is "twenty-one billion, one million, three hundred thirty-two thousand, two hundred thirty-three".