21333123100 has 72 divisors (see below), whose sum is σ = 47158544160. Its totient is φ = 8375162880.

The previous prime is 21333123089. The next prime is 21333123109. The reversal of 21333123100 is 132133312.

It is a super-2 number, since 2×21333123100² (a number of 21 digits) contains 22 as substring.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21333123109) 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 23 ways as a sum of consecutive naturals, for example, 1154736 + ... + 1173064.

It is an arithmetic number, because the mean of its divisors is an integer number (654979780).

Almost surely, 2^21333123100 is an apocalyptic number.

21333123100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21333123100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23579272080).

21333123100 is an abundant number, since it is smaller than the sum of its proper divisors (25825421060).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

21333123100 is a wasteful number, since it uses less digits than its factorization.

21333123100 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 18559 (or 18552 counting only the distinct ones).

The product of its (nonzero) digits is 324, while the sum is 19.

Adding to 21333123100 its reverse (132133312), we get a palindrome (21465256412).

The spelling of 21333123100 in words is "twenty-one billion, three hundred thirty-three million, one hundred twenty-three thousand, one hundred".