1223222220 has 288 divisors, whose sum is σ = 4242551040. Its totient is φ = 282631680.

The previous prime is 1223222219. The next prime is 1223222243. The reversal of 1223222220 is 222223221.

1223222220 is a `hidden beast` number, since 1 + 223 + 222 + 220 = 666.

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 = 1223222193 and 1223222202.

It is an unprimeable number.

It is a polite number, since it can be written in 95 ways as a sum of consecutive naturals, for example, 4322199 + ... + 4322481.

It is an arithmetic number, because the mean of its divisors is an integer number (14731080).

Almost surely, 2^1223222220 is an apocalyptic number.

1223222220 is a gapful number since it is divisible by the number (10) 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 1223222220, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (2121275520).

1223222220 is an abundant number, since it is smaller than the sum of its proper divisors (3019328820).

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

1223222220 is a wasteful number, since it uses less digits than its factorization.

1223222220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 405 (or 400 counting only the distinct ones).

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

The square root of 1223222220 is about 34974.5939218742. The cubic root of 1223222220 is about 1069.4696238915.

Adding to 1223222220 its reverse (222223221), we get a palindrome (1445445441).

It can be divided in two parts, 12 and 23222220, that added together give a palindrome (23222232).

The spelling of 1223222220 in words is "one billion, two hundred twenty-three million, two hundred twenty-two thousand, two hundred twenty".