21232333021 has 32 divisors (see below), whose sum is σ = 22651278048. Its totient is φ = 19878543360.

The previous prime is 21232332997. The next prime is 21232333099. The reversal of 21232333021 is 12033323212.

It can be written as a sum of positive squares in 16 ways, for example, as 994140900 + 20238192121 = 31530^2 + 142261^2 .

It is a cyclic number.

It is a de Polignac number, because none of the positive numbers 2^k-21232333021 is a prime.

It is a Duffinian number.

It is a junction number, because it is equal to n+sod(n) for n = 21232332983 and 21232333001.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21232333621) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 21731685 + ... + 21732661.

It is an arithmetic number, because the mean of its divisors is an integer number (707852439).

Almost surely, 2^21232333021 is an apocalyptic number.

It is an amenable number.

21232333021 is a deficient number, since it is larger than the sum of its proper divisors (1418945027).

21232333021 is a wasteful number, since it uses less digits than its factorization.

21232333021 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 1281.

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

Adding to 21232333021 its reverse (12033323212), we get a palindrome (33265656233).

The spelling of 21232333021 in words is "twenty-one billion, two hundred thirty-two million, three hundred thirty-three thousand, twenty-one".