21200212121200 has 120 divisors (see below), whose sum is σ = 58212094500000. Its totient is φ = 7268348313600.

The previous prime is 21200212121177. The next prime is 21200212121201. The reversal of 21200212121200 is 212121200212.

It is a happy number.

It is a Harshad number since it is a multiple of its sum of digits (16).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (21200212121201) 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, 75238176 + ... + 75519424.

It is an arithmetic number, because the mean of its divisors is an integer number (485100787500).

Almost surely, 2^{21200212121200} is an apocalyptic number.

21200212121200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21200212121200 is an abundant number, since it is smaller than the sum of its proper divisors (37011882378800).

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

21200212121200 is a wasteful number, since it uses less digits than its factorization.

21200212121200 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 308195 (or 308184 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

Adding to 21200212121200 its reverse (212121200212), we get a palindrome (21412333321412).

The spelling of 21200212121200 in words is "twenty-one trillion, two hundred billion, two hundred twelve million, one hundred twenty-one thousand, two hundred".