21211021121200 has 60 divisors (see below), whose sum is σ = 51005932788600. Its totient is φ = 8476674081280.

The previous prime is 21211021121177. The next prime is 21211021121207. The reversal of 21211021121200 is 212112011212.

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

It is not an unprimeable number, because it can be changed into a prime (21211021121207) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (19) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 23730550 + ... + 24608149.

It is an arithmetic number, because the mean of its divisors is an integer number (850098879810).

Almost surely, 2^{21211021121200} is an apocalyptic number.

21211021121200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21211021121200 is an abundant number, since it is smaller than the sum of its proper divisors (29794911667400).

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

21211021121200 is a wasteful number, since it uses less digits than its factorization.

21211021121200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 48339814 (or 48339803 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 16.

Adding to 21211021121200 its reverse (212112011212), we get a palindrome (21423133132412).

The spelling of 21211021121200 in words is "twenty-one trillion, two hundred eleven billion, twenty-one million, one hundred twenty-one thousand, two hundred".