21002202121100 has 72 divisors (see below), whose sum is σ = 46320249428880. Its totient is φ = 8263820632320.

The previous prime is 21002202121091. The next prime is 21002202121193. The reversal of 21002202121100 is 112120220012.

It is an unprimeable number.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 2539682 + ... + 6960918.

Almost surely, 2^{21002202121100} is an apocalyptic number.

21002202121100 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 21002202121100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (23160124714440).

21002202121100 is an abundant number, since it is smaller than the sum of its proper divisors (25318047307780).

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

21002202121100 is a wasteful number, since it uses less digits than its factorization.

21002202121100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4422027 (or 4422020 counting only the distinct ones).

The product of its (nonzero) digits is 32, while the sum is 14.

Adding to 21002202121100 its reverse (112120220012), we get a palindrome (21114322341112).

The spelling of 21002202121100 in words is "twenty-one trillion, two billion, two hundred two million, one hundred twenty-one thousand, one hundred".