21123104200 has 96 divisors (see below), whose sum is σ = 53936280000. Its totient is φ = 7629459200.

The previous prime is 21123104179. The next prime is 21123104207. The reversal of 21123104200 is 240132112.

It is not an unprimeable number, because it can be changed into a prime (21123104207) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 295581 + ... + 360019.

It is an arithmetic number, because the mean of its divisors is an integer number (561836250).

Almost surely, 2^21123104200 is an apocalyptic number.

21123104200 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 21123104200, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26968140000).

21123104200 is an abundant number, since it is smaller than the sum of its proper divisors (32813175800).

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

21123104200 is a wasteful number, since it uses less digits than its factorization.

21123104200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 64615 (or 64606 counting only the distinct ones).

The product of its (nonzero) digits is 96, while the sum is 16.

Adding to 21123104200 its reverse (240132112), we get a palindrome (21363236312).

The spelling of 21123104200 in words is "twenty-one billion, one hundred twenty-three million, one hundred four thousand, two hundred".