2221223220 has 72 divisors (see below), whose sum is σ = 6919831464. Its totient is φ = 576315648.

The previous prime is 2221223203. The next prime is 2221223233. The reversal of 2221223220 is 223221222.

2221223220 is a `hidden beast` number, since 2 + 221 + 223 + 220 = 666.

It can be written as a sum of positive squares in 4 ways, for example, as 107246736 + 2113976484 = 10356^2 + 45978^2 .

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 = 2221223193 and 2221223202.

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, 160099 + ... + 173418.

Almost surely, 2^2221223220 is an apocalyptic number.

2221223220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

2221223220 is an abundant number, since it is smaller than the sum of its proper divisors (4698608244).

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

2221223220 is a wasteful number, since it uses less digits than its factorization.

2221223220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 333569 (or 333564 counting only the distinct ones).

The product of its (nonzero) digits is 384, while the sum is 18.

The square root of 2221223220 is about 47129.8548692864. The cubic root of 2221223220 is about 1304.7603030057.

Adding to 2221223220 its reverse (223221222), we get a palindrome (2444444442).

The spelling of 2221223220 in words is "two billion, two hundred twenty-one million, two hundred twenty-three thousand, two hundred twenty".