21333232221 has 32 divisors (see below), whose sum is σ = 34760855808. Its totient is φ = 11359718400.

The previous prime is 21333232181. The next prime is 21333232229. The reversal of 21333232221 is 12223233312.

It is not a de Polignac number, because 21333232221 - 2⁶ = 21333232157 is a prime.

It is a super-2 number, since 2×21333232221² (a number of 21 digits) contains 22 as substring.

It is a junction number, because it is equal to n+sod(n) for n = 21333232191 and 21333232200.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21333232229) 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, 259770 + ... + 331883.

It is an arithmetic number, because the mean of its divisors is an integer number (1086276744).

Almost surely, 2^21333232221 is an apocalyptic number.

21333232221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

21333232221 is a deficient number, since it is larger than the sum of its proper divisors (13427623587).

21333232221 is a wasteful number, since it uses less digits than its factorization.

21333232221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 591781.

The product of its digits is 2592, while the sum is 24.

Adding to 21333232221 its reverse (12223233312), we get a palindrome (33556465533).

The spelling of 21333232221 in words is "twenty-one billion, three hundred thirty-three million, two hundred thirty-two thousand, two hundred twenty-one".