21323203200 has 576 divisors, whose sum is σ = 82668276600. Its totient is φ = 5233213440.

The previous prime is 21323203183. The next prime is 21323203219. The reversal of 21323203200 is 230232312.

It is a happy number.

21323203200 is a `hidden beast` number, since 2 + 1 + 323 + 20 + 320 + 0 = 666.

It can be written as a sum of positive squares in 12 ways, for example, as 11982367296 + 9340835904 = 109464^2 + 96648^2 .

It is a tau number, because it is divible by the number of its divisors (576).

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 71 ways as a sum of consecutive naturals, for example, 63273432 + ... + 63273768.

Almost surely, 2^21323203200 is an apocalyptic number.

21323203200 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 21323203200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (41334138300).

21323203200 is an abundant number, since it is smaller than the sum of its proper divisors (61345073400).

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

21323203200 is a wasteful number, since it uses less digits than its factorization.

21323203200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 406 (or 360 counting only the distinct ones).

The product of its (nonzero) digits is 432, while the sum is 18.

Adding to 21323203200 its reverse (230232312), we get a palindrome (21553435512).

The spelling of 21323203200 in words is "twenty-one billion, three hundred twenty-three million, two hundred three thousand, two hundred".