21323124200 has 144 divisors (see below), whose sum is σ = 59078054700. Its totient is φ = 7132339200.

The previous prime is 21323124197. The next prime is 21323124209. The reversal of 21323124200 is 242132312.

It can be written as a sum of positive squares in 6 ways, for example, as 8801066596 + 12522057604 = 93814^2 + 111902^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is not an unprimeable number, because it can be changed into a prime (21323124209) by changing a digit.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 375266 + ... + 428334.

Almost surely, 2^21323124200 is an apocalyptic number.

21323124200 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 21323124200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (29539027350).

21323124200 is an abundant number, since it is smaller than the sum of its proper divisors (37754930500).

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

21323124200 is a wasteful number, since it uses less digits than its factorization.

21323124200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 53140 (or 53124 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 21323124200 its reverse (242132312), we get a palindrome (21565256512).

The spelling of 21323124200 in words is "twenty-one billion, three hundred twenty-three million, one hundred twenty-four thousand, two hundred".