21001220200002 has 128 divisors (see below), whose sum is σ = 49430920992768. Its totient is φ = 5822709235200.

The previous prime is 21001220199991. The next prime is 21001220200003. The reversal of 21001220200002 is 20000202210012.

It is not an unprimeable number, because it can be changed into a prime (21001220200003) 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 63 ways as a sum of consecutive naturals, for example, 1200678477 + ... + 1200695967.

It is an arithmetic number, because the mean of its divisors is an integer number (386179070256).

Almost surely, 2^{21001220200002} is an apocalyptic number.

It is a practical number, because each smaller number is the sum of distinct divisors of 21001220200002, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (24715460496384).

21001220200002 is an abundant number, since it is smaller than the sum of its proper divisors (28429700792766).

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

21001220200002 is a wasteful number, since it uses less digits than its factorization.

21001220200002 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 19544.

The product of its (nonzero) digits is 32, while the sum is 12.

Adding to 21001220200002 its reverse (20000202210012), we get a palindrome (41001422410014).

The spelling of 21001220200002 in words is "twenty-one trillion, one billion, two hundred twenty million, two hundred thousand, two".