2211218820 has 36 divisors (see below), whose sum is σ = 6707364300. Its totient is φ = 589658304.

The previous prime is 2211218819. The next prime is 2211218831. The reversal of 2211218820 is 288121122.

It can be written as a sum of positive squares in 2 ways, for example, as 694427904 + 1516790916 = 26352^2 + 38946^2 .

It is a tau number, because it is divible by the number of its divisors (36).

It is an unprimeable number.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 6142095 + ... + 6142454.

It is an arithmetic number, because the mean of its divisors is an integer number (186315675).

Almost surely, 2^2211218820 is an apocalyptic number.

2211218820 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2211218820 is an abundant number, since it is smaller than the sum of its proper divisors (4496145480).

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

2211218820 is a wasteful number, since it uses less digits than its factorization.

2211218820 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 12284564 (or 12284559 counting only the distinct ones).

The product of its (nonzero) digits is 1024, while the sum is 27.

The square root of 2211218820 is about 47023.5985437099. The cubic root of 2211218820 is about 1302.7984724726.

Adding to 2211218820 its reverse (288121122), we get a palindrome (2499339942).

The spelling of 2211218820 in words is "two billion, two hundred eleven million, two hundred eighteen thousand, eight hundred twenty".