2001222221200 has 60 divisors (see below), whose sum is σ = 4973727325140. Its totient is φ = 772885818880.

The previous prime is 2001222221161. The next prime is 2001222221209. The reversal of 2001222221200 is 21222221002.

It can be written as a sum of positive squares in 6 ways, for example, as 59012069776 + 1942210151424 = 242924^2 + 1393632^2 .

It is a Harshad number since it is a multiple of its sum of digits (16).

It is not an unprimeable number, because it can be changed into a prime (2001222221209) by changing a digit.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 86247979 + ... + 86271178.

It is an arithmetic number, because the mean of its divisors is an integer number (82895455419).

Almost surely, 2^{2001222221200} is an apocalyptic number.

2001222221200 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2001222221200 is an abundant number, since it is smaller than the sum of its proper divisors (2972505103940).

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

2001222221200 is a wasteful number, since it uses less digits than its factorization.

2001222221200 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 172519204 (or 172519193 counting only the distinct ones).

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

Adding to 2001222221200 its reverse (21222221002), we get a palindrome (2022444442202).

The spelling of 2001222221200 in words is "two trillion, one billion, two hundred twenty-two million, two hundred twenty-one thousand, two hundred".