20330221 has 4 divisors (see below), whose sum is σ = 20340000. Its totient is φ = 20320444.

The previous prime is 20330207. The next prime is 20330237. The reversal of 20330221 is 12203302.

It is a happy number.

It is a semiprime because it is the product of two primes, and also a Blum integer, because the two primes are equal to 3 mod 4, and also a brilliant number, because the two primes have the same length, and also an emirpimes, since its reverse is a distinct semiprime: 12203302 = 2 ⋅6101651.

It is a cyclic number.

It is not a de Polignac number, because 20330221 - 2²³ = 11941613 is a prime.

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20330201) by changing a digit.

It is a polite number, since it can be written in 3 ways as a sum of consecutive naturals, for example, 391 + ... + 6388.

It is an arithmetic number, because the mean of its divisors is an integer number (5085000).

Almost surely, 2^20330221 is an apocalyptic number.

It is an amenable number.

20330221 is a deficient number, since it is larger than the sum of its proper divisors (9779).

20330221 is an equidigital number, since it uses as much as digits as its factorization.

20330221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 9778.

The product of its (nonzero) digits is 72, while the sum is 13.

The square root of 20330221 is about 4508.9046341656. The cubic root of 20330221 is about 272.9275436438.

Adding to 20330221 its reverse (12203302), we get a palindrome (32533523).

The spelling of 20330221 in words is "twenty million, three hundred thirty thousand, two hundred twenty-one".