2001222221100 has 72 divisors (see below), whose sum is σ = 5793530263248. Its totient is φ = 533352595200.

The previous prime is 2001222221087. The next prime is 2001222221161. The reversal of 2001222221100 is 11222221002.

It is a Harshad number since it is a multiple of its sum of digits (15).

It is a self number, because there is not a number n which added to its sum of digits gives 2001222221100.

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, 1393479 + ... + 2438078.

Almost surely, 2^{2001222221100} is an apocalyptic number.

2001222221100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2001222221100 is an abundant number, since it is smaller than the sum of its proper divisors (3792308042148).

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

2001222221100 is a wasteful number, since it uses less digits than its factorization.

2001222221100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 3833315 (or 3833308 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 15.

Adding to 2001222221100 its reverse (11222221002), we get a palindrome (2012444442102).

The spelling of 2001222221100 in words is "two trillion, one billion, two hundred twenty-two million, two hundred twenty-one thousand, one hundred".