2011220100 has 108 divisors (see below), whose sum is σ = 6474544804. Its totient is φ = 521821440.

The previous prime is 2011220069. The next prime is 2011220117. The reversal of 2011220100 is 10221102.

It can be written as a sum of positive squares in 6 ways, for example, as 7225344 + 2003994756 = 2688^2 + 44766^2 .

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a congruent number.

It is an unprimeable number.

It is a polite number, since it can be written in 35 ways as a sum of consecutive naturals, for example, 3102 + ... + 63498.

Almost surely, 2^2011220100 is an apocalyptic number.

2011220100 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 2011220100, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3237272402).

2011220100 is an abundant number, since it is smaller than the sum of its proper divisors (4463324704).

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

2011220100 is a wasteful number, since it uses less digits than its factorization.

2011220100 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 60454 (or 60444 counting only the distinct ones).

The product of its (nonzero) digits is 8, while the sum is 9.

The square root of 2011220100 is about 44846.6286358295. The cubic root of 2011220100 is about 1262.2727310411.

Adding to 2011220100 its reverse (10221102), we get a palindrome (2021441202).

It can be divided in two parts, 2011 and 220100, that added together give a triangular number (222111 = T₆₆₆).

The spelling of 2011220100 in words is "two billion, eleven million, two hundred twenty thousand, one hundred".