21124200000 has 672 divisors, whose sum is σ = 78576220800. Its totient is φ = 4976640000.

The previous prime is 21124199977. The next prime is 21124200007. The reversal of 21124200000 is 242112.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is not an unprimeable number, because it can be changed into a prime (21124200007) by changing a digit.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 193799946 + ... + 193800054.

It is an arithmetic number, because the mean of its divisors is an integer number (116928900).

Almost surely, 2^21124200000 is an apocalyptic number.

21124200000 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 21124200000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (39288110400).

21124200000 is an abundant number, since it is smaller than the sum of its proper divisors (57452020800).

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

21124200000 is a wasteful number, since it uses less digits than its factorization.

21124200000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 185 (or 155 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 21124200000 its reverse (242112), we get a palindrome (21124442112).

The spelling of 21124200000 in words is "twenty-one billion, one hundred twenty-four million, two hundred thousand".