2205211820 has 72 divisors (see below), whose sum is σ = 5585850144. Its totient is φ = 716262912.

The previous prime is 2205211807. The next prime is 2205211843. The reversal of 2205211820 is 281125022.

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, 28724 + ... + 72356.

It is an arithmetic number, because the mean of its divisors is an integer number (77581252).

Almost surely, 2^2205211820 is an apocalyptic number.

2205211820 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 2205211820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2792925072).

2205211820 is an abundant number, since it is smaller than the sum of its proper divisors (3380638324).

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

2205211820 is a wasteful number, since it uses less digits than its factorization.

2205211820 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 43687 (or 43666 counting only the distinct ones).

The product of its (nonzero) digits is 640, while the sum is 23.

The square root of 2205211820 is about 46959.6829205650. The cubic root of 2205211820 is about 1301.6176745503.

Adding to 2205211820 its reverse (281125022), we get a palindrome (2486336842).

The spelling of 2205211820 in words is "two billion, two hundred five million, two hundred eleven thousand, eight hundred twenty".