20200221 has 12 divisors (see below), whose sum is σ = 29548480. Its totient is φ = 13295880.

The previous prime is 20200181. The next prime is 20200223. The reversal of 20200221 is 12200202.

It is not a de Polignac number, because 20200221 - 2⁶ = 20200157 is a prime.

It is a Harshad number since it is a multiple of its sum of digits (9).

It is a Duffinian number.

It is a congruent number.

It is not an unprimeable number, because it can be changed into a prime (20200223) by changing a digit.

It is a pernicious number, because its binary representation contains a prime number (13) of ones.

It is a polite number, since it can be written in 11 ways as a sum of consecutive naturals, for example, 13495 + ... + 14916.

Almost surely, 2^20200221 is an apocalyptic number.

It is an amenable number.

20200221 is a deficient number, since it is larger than the sum of its proper divisors (9348259).

20200221 is a wasteful number, since it uses less digits than its factorization.

20200221 is an odious number, because the sum of its binary digits is odd.

The sum of its prime factors is 28496 (or 28493 counting only the distinct ones).

The product of its (nonzero) digits is 16, while the sum is 9.

The square root of 20200221 is about 4494.4655967089. The cubic root of 20200221 is about 272.3445613534.

Adding to 20200221 its reverse (12200202), we get a palindrome (32400423).

The spelling of 20200221 in words is "twenty million, two hundred thousand, two hundred twenty-one".