20380221 has 16 divisors (see below), whose sum is σ = 30357120. Its totient is φ = 13512960.

The previous prime is 20380219. The next prime is 20380253. The reversal of 20380221 is 12208302.

It is a happy number.

It is not a de Polignac number, because 20380221 - 2¹ = 20380219 is a prime.

It is a junction number, because it is equal to n+sod(n) for n = 20380194 and 20380203.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20380211) 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, 3256 + ... + 7166.

It is an arithmetic number, because the mean of its divisors is an integer number (1897320).

Almost surely, 2^20380221 is an apocalyptic number.

It is an amenable number.

20380221 is a deficient number, since it is larger than the sum of its proper divisors (9976899).

20380221 is a wasteful number, since it uses less digits than its factorization.

20380221 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4113 (or 4107 counting only the distinct ones).

The product of its (nonzero) digits is 192, while the sum is 18.

The square root of 20380221 is about 4514.4458131647. The cubic root of 20380221 is about 273.1511058172.

Adding to 20380221 its reverse (12208302), we get a palindrome (32588523).

The spelling of 20380221 in words is "twenty million, three hundred eighty thousand, two hundred twenty-one".