2001222222100 has 72 divisors (see below), whose sum is σ = 4489384145400. Its totient is φ = 773799782400.

The previous prime is 2001222222061. The next prime is 2001222222119. The reversal of 2001222222100 is 12222221002.

It can be written as a sum of positive squares in 12 ways, for example, as 751973402896 + 1249248819204 = 867164^2 + 1117698^2 .

It is a congruent number.

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, 1792105 + ... + 2685904.

It is an arithmetic number, because the mean of its divisors is an integer number (62352557575).

Almost surely, 2^{2001222222100} is an apocalyptic number.

2001222222100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2001222222100 is an abundant number, since it is smaller than the sum of its proper divisors (2488161923300).

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

2001222222100 is a wasteful number, since it uses less digits than its factorization.

2001222222100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4478173 (or 4478166 counting only the distinct ones).

The product of its (nonzero) digits is 128, while the sum is 16.

Adding to 2001222222100 its reverse (12222221002), we get a palindrome (2013444443102).

The spelling of 2001222222100 in words is "two trillion, one billion, two hundred twenty-two million, two hundred twenty-two thousand, one hundred".