21002122100220 has 96 divisors (see below), whose sum is σ = 61902933523200. Its totient is φ = 5305632804864.

The previous prime is 21002122100171. The next prime is 21002122100243. The reversal of 21002122100220 is 2200122120012.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 21002122100220.

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 31 ways as a sum of consecutive naturals, for example, 38324911 + ... + 38869049.

It is an arithmetic number, because the mean of its divisors is an integer number (644822224200).

Almost surely, 2^{21002122100220} is an apocalyptic number.

21002122100220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

21002122100220 is an abundant number, since it is smaller than the sum of its proper divisors (40900811422980).

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

21002122100220 is a wasteful number, since it uses less digits than its factorization.

21002122100220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 578027 (or 578025 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 21002122100220 its reverse (2200122120012), we get a palindrome (23202244220232).

The spelling of 21002122100220 in words is "twenty-one trillion, two billion, one hundred twenty-two million, one hundred thousand, two hundred twenty".