2001221102100 has 288 divisors, whose sum is σ = 6449954426496. Its totient is φ = 474998169600.

The previous prime is 2001221102077. The next prime is 2001221102117. The reversal of 2001221102100 is 12011221002.

It is a Harshad number since it is a multiple of its sum of digits (12).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 32972982 + ... + 33033618.

It is an arithmetic number, because the mean of its divisors is an integer number (22395675092).

Almost surely, 2^{2001221102100} is an apocalyptic number.

2001221102100 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 2001221102100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3224977213248).

2001221102100 is an abundant number, since it is smaller than the sum of its proper divisors (4448733324396).

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

2001221102100 is a wasteful number, since it uses less digits than its factorization.

2001221102100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60875 (or 60868 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 12.

Adding to 2001221102100 its reverse (12011221002), we get a palindrome (2013232323102).

It can be divided in two parts, 20012 and 21102100, that added together give a palindrome (21122112).

The spelling of 2001221102100 in words is "two trillion, one billion, two hundred twenty-one million, one hundred two thousand, one hundred".