20332221 has 48 divisors (see below), whose sum is σ = 35627904. Its totient is φ = 10063872.

The previous prime is 20332217. The next prime is 20332229. The reversal of 20332221 is 12223302.

It is not a de Polignac number, because 20332221 - 2² = 20332217 is a prime.

It is a self number, because there is not a number n which added to its sum of digits gives 20332221.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20332229) by changing a digit.

It is a polite number, since it can be written in 47 ways as a sum of consecutive naturals, for example, 60165 + ... + 60501.

It is an arithmetic number, because the mean of its divisors is an integer number (742248).

Almost surely, 2^20332221 is an apocalyptic number.

20332221 is a gapful number since it is divisible by the number (21) formed by its first and last digit.

It is an amenable number.

20332221 is a deficient number, since it is larger than the sum of its proper divisors (15295683).

20332221 is a wasteful number, since it uses less digits than its factorization.

20332221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 390 (or 377 counting only the distinct ones).

The product of its (nonzero) digits is 144, while the sum is 15.

The square root of 20332221 is about 4509.1264120670. The cubic root of 20332221 is about 272.9364931643.

Adding to 20332221 its reverse (12223302), we get a palindrome (32555523).

The spelling of 20332221 in words is "twenty million, three hundred thirty-two thousand, two hundred twenty-one".