623221221 has 24 divisors (see below), whose sum is σ = 963030720. Its totient is φ = 351184896.

The previous prime is 623221219. The next prime is 623221237. The reversal of 623221221 is 122122326.

623221221 is digitally balanced in base 2, because in such base it contains all the possibile digits an equal number of times.

It is not a de Polignac number, because 623221221 - 2¹ = 623221219 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (21).

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (623223221) by changing a digit.

It is a polite number, since it can be written in 23 ways as a sum of consecutive naturals, for example, 109125 + ... + 114693.

It is an arithmetic number, because the mean of its divisors is an integer number (40126280).

Almost surely, 2^623221221 is an apocalyptic number.

It is an amenable number.

623221221 is a deficient number, since it is larger than the sum of its proper divisors (339809499).

623221221 is an equidigital number, since it uses as much as digits as its factorization.

623221221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 5725 (or 5652 counting only the distinct ones).

The product of its digits is 576, while the sum is 21.

The square root of 623221221 is about 24964.3990714778. The cubic root of 623221221 is about 854.1760908176.

Adding to 623221221 its reverse (122122326), we get a palindrome (745343547).

The spelling of 623221221 in words is "six hundred twenty-three million, two hundred twenty-one thousand, two hundred twenty-one".