221223220 has 48 divisors (see below), whose sum is σ = 477042048. Its totient is φ = 86145920.

The previous prime is 221223209. The next prime is 221223221. The reversal of 221223220 is 22322122.

It is a junction number, because it is equal to n+sod(n) for n = 221223194 and 221223203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (221223221) 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, 116922 + ... + 118798.

It is an arithmetic number, because the mean of its divisors is an integer number (9938376).

Almost surely, 2^221223220 is an apocalyptic number.

221223220 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

221223220 is an abundant number, since it is smaller than the sum of its proper divisors (255818828).

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

221223220 is a wasteful number, since it uses less digits than its factorization.

221223220 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 2040 (or 2038 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 16.

The square root of 221223220 is about 14873.5745535497. The cubic root of 221223220 is about 604.7978469929.

Adding to 221223220 its reverse (22322122), we get a palindrome (243545342).

The spelling of 221223220 in words is "two hundred twenty-one million, two hundred twenty-three thousand, two hundred twenty".