2221331220 has 72 divisors (see below), whose sum is σ = 6753626880. Its totient is φ = 590984640.

The previous prime is 2221331213. The next prime is 2221331239. The reversal of 2221331220 is 221331222.

It is a Harshad number since it is a multiple of its sum of digits (18).

It is a junction number, because it is equal to n+sod(n) for n = 2221331193 and 2221331202.

It is a congruent number.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 64965 + ... + 93075.

Almost surely, 2^2221331220 is an apocalyptic number.

2221331220 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 2221331220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (3376813440).

2221331220 is an abundant number, since it is smaller than the sum of its proper divisors (4532295660).

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

2221331220 is a wasteful number, since it uses less digits than its factorization.

2221331220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28565 (or 28560 counting only the distinct ones).

The product of its (nonzero) digits is 288, while the sum is 18.

The square root of 2221331220 is about 47131.0006259150. Note that the first 3 decimals coincide. The cubic root of 2221331220 is about 1304.7814492864.

Adding to 2221331220 its reverse (221331222), we get a palindrome (2442662442).

The spelling of 2221331220 in words is "two billion, two hundred twenty-one million, three hundred thirty-one thousand, two hundred twenty".