2211820 has 48 divisors (see below), whose sum is σ = 5136768. Its totient is φ = 794880.

The previous prime is 2211817. The next prime is 2211821. The reversal of 2211820 is 281122.

2211820 is digitally balanced in base 5, because in such base it contains all the possibile digits an equal number of times.

It is a junction number, because it is equal to n+sod(n) for n = 2211794 and 2211803.

It is not an unprimeable number, because it can be changed into a prime (2211821) by changing a digit.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 12130 + ... + 12310.

It is an arithmetic number, because the mean of its divisors is an integer number (107016).

2^2211820 is an apocalyptic number.

2211820 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 2211820, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2568384).

2211820 is an abundant number, since it is smaller than the sum of its proper divisors (2924948).

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

2211820 is a wasteful number, since it uses less digits than its factorization.

2211820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 250 (or 248 counting only the distinct ones).

The product of its (nonzero) digits is 64, while the sum is 16.

The square root of 2211820 is about 1487.2188809990. The cubic root of 2211820 is about 130.2916528845.

Adding to 2211820 its reverse (281122), we get a palindrome (2492942).

The spelling of 2211820 in words is "two million, two hundred eleven thousand, eight hundred twenty".