2001222100 has 36 divisors (see below), whose sum is σ = 4345152448. Its totient is φ = 800028000.

The previous prime is 2001222089. The next prime is 2001222103. The reversal of 2001222100 is 12221002.

It is a Harshad number since it is a multiple of its sum of digits (10).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (2001222103) 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, 208405 + ... + 217795.

Almost surely, 2^2001222100 is an apocalyptic number.

2001222100 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2001222100 is an abundant number, since it is smaller than the sum of its proper divisors (2343930348).

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

2001222100 is a wasteful number, since it uses less digits than its factorization.

2001222100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 11536 (or 11529 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 10.

The square root of 2001222100 is about 44735.0209567404. The cubic root of 2001222100 is about 1260.1776225616.

Adding to 2001222100 its reverse (12221002), we get a palindrome (2013443102).

The spelling of 2001222100 in words is "two billion, one million, two hundred twenty-two thousand, one hundred".