221223201320 has 96 divisors (see below), whose sum is σ = 552757602600. Its totient is φ = 79615303680.

The previous prime is 221223201253. The next prime is 221223201371. The reversal of 221223201320 is 23102322122.

It is a happy number.

It can be written as a sum of positive squares in 4 ways, for example, as 126535295524 + 94687905796 = 355718^2 + 307714^2 .

It is a Harshad number since it is a multiple of its sum of digits (20).

It is a junction number, because it is equal to n+sod(n) for n = 221223201292 and 221223201301.

It is an unprimeable number.

It is a pernicious number, because its binary representation contains a prime number (17) of ones.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 233876 + ... + 705084.

Almost surely, 2^221223201320 is an apocalyptic number.

221223201320 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 221223201320, and also a Zumkeller number, because its divisors can be partitioned in two sets with the same sum (276378801300).

221223201320 is an abundant number, since it is smaller than the sum of its proper divisors (331534401280).

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

221223201320 is a wasteful number, since it uses less digits than its factorization.

221223201320 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 471339 (or 471324 counting only the distinct ones).

The product of its (nonzero) digits is 576, while the sum is 20.

Adding to 221223201320 its reverse (23102322122), we get a palindrome (244325523442).

The spelling of 221223201320 in words is "two hundred twenty-one billion, two hundred twenty-three million, two hundred one thousand, three hundred twenty".