21200020012000 has 96 divisors (see below), whose sum is σ = 52124965270560. Its totient is φ = 8474063180800.

The previous prime is 21200020011979. The next prime is 21200020012001. The reversal of 21200020012000 is 21002000212.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200020012001) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 3850956 + ... + 7565044.

It is an arithmetic number, because the mean of its divisors is an integer number (542968388235).

Almost surely, 2^{21200020012000} is an apocalyptic number.

21200020012000 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 21200020012000, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (26062482635280).

21200020012000 is an abundant number, since it is smaller than the sum of its proper divisors (30924945258560).

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

21200020012000 is a wasteful number, since it uses less digits than its factorization.

21200020012000 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3715541 (or 3715523 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

Adding to 21200020012000 its reverse (21002000212), we get a palindrome (21221022012212).

The spelling of 21200020012000 in words is "twenty-one trillion, two hundred billion, twenty million, twelve thousand".